Apple has released the developer preview of OS X 10.8 Mountain Lion, just seven months after the acclaimed launch of Lion.

The latest version of the Mac OS will port a number of key features from the iOS platform to Apple's desktops and laptops, bringing all devices a step closer to unification in terms of user experience. We take a look at the top five features that are set to be included.

5. Twitter integration
The popularity of Twitter has already led to Apple integrating the social networking site into its mobile OS. This will now be extended to Macs and make it quicker and easier to share posts. Users will be able to tweet from native apps such as Safari, Quick Look and Photo Booth and a host of third-party apps are also expected to include this functionality. Anything that removes extra steps is always a good thing.

4. iCloud syncing
Apple has noted that Mountain Lion has been developed with the iCloud in mind and users will find it easier to set up and sync content between devices using their Mac. No details have been given about how this will be made easier, but we expect Apple to remain true to its word.

3. Gatekeeper
With the increased use of apps on Apple desktop OS, the firm is keen to plug any potential security holes. Apple will launch the Gatekeeper app, a security feature that allows users to monitor apps that have been downloaded and installed on a Mac.

Users will be able to install apps from any source if they wish, or lock down their system so that only vetted apps from the Mac App Store will be usable.

2. Messages and Notifications Center
The Messages app will replace the iChat client and enable Mac users to send unlimited messages, photos and videos to any other Mac or iOS device over the net. Messages will also retain support for other popular IM clients including AIM, Jabber, Yahoo Messenger and Google Talk. Lion users can download a beta version of Messages from www.apple.com, and give it a test-drive.

Mountain Lion also introduces the Notifications Center to the Mac interface. This dropdown menu will include alerts such as emails and friend requests. It will be interesting to see exactly how this dropdown bar is triggered on Mac devices, though. On the iPhone and iPad it is activated by a swipe of the touch screen. The inclusion of the Notification Center could be an indication that Apple may be planning to add touch screens to its OS X-based devices.

1. Airplay streaming
OS X Mountain Lion will bring AirPlay Mirroring to the Mac platform. Users will be able to securely stream 720p video streams over wireless from a Mac to an HDTV using Apple TV. This will be particularly convenient for users who are using MacBooks and want to view multimedia content on larger screens, and is likely to boost sales of Apple TV.

Siri?
We'd like to point out that Siri, the voice activated personal assistant that debuted on the iPhone 4S, is not going to be included. It is still officially in the beta phase, so we're not too surprised it hasn't been included. But stranger things have happened and it could still be added to the final release of Mountain Lion.

Apple unleashed the latest version of OS X Lion to the masses a little over two weeks ago, introducing a number of key features in the process. V3 has had a chance to get to grips with Lion on Apple's 11in MacBook Air and we've picked out some of the key features that will help you to get the most out of your Mac.

1. Use swiping gestures with multiple desktops
The trackpad has been redefined, allowing a number of swiping gestures using two and three fingers.

Scrolling and pinch-to-zoom are welcome features, and work remarkably well on the trackpad. However, we've found the most useful gesture to be the three-fingered horizontal swipe that allows you to navigate between full screen applications. A nifty way to use this is to create multiple desktops, which you can then cycle between.

To do this, you simply bring up Mission Control, add another desktop by hovering the mouse over the top right hand corner and then populate that desktop with specific apps. You can then keep internet windows in one desktop, word documents in the second, mail in the third and handily cross-reference between them with a single swipe.

2. Use Thunderbolt to transport data
Apple has been heavily promoting this feature over the past few months and it's now usable in the latest Mac devices. Thunderbolt allows high-speed transfer between two Apple Mac devices. We were able to use the port to transfer data from a MacBook Air to a Mac Mini.

To do this we had to set up the MacBook as an external hard drive by activating Target Disk Mode.

This was done by connecting the Thunderbolt cable and holding down the letter 'T' when booting up the Air. The Thunderbolt icon displayed on the screen of the MacBook and the device appeared as an external hard drive on the host - in this case the Mac Mini.

To give you an idea of Thunderbolt's speed, we transferred a 1.27GB file between Macs in just under two minutes. The same transfer took 15 minutes to load onto a USB stick and around 50 minutes to complete via AirDrop.

3. Sync revamped Mail app with Outlook
Apple has revamped its Mail feature, and the application now mirrors the iPad two-column interface. We like the conversation-style thread, which separates messages cleanly, and the full screen view.

However, the best feature by far is the dynamic search which automatically brings up suggestions when you start typing in a person's name or subject. This makes searching painless as relevant messages are instantly displayed. Finding the right email is considerably faster than using the search in traditional Outlook and Lotus Notes clients.

V3 also managed to synchronise corporate email from an Exchange 2003 server within the native Mail app. This was done by setting up an email account and choosing 'IMAP' as the account type. We then entered the IP address of the Incoming Mail Server, along with our username and password.

Alternatively, it is possible to download apps such as Mail Access 2003 from the Mac Store to get comprehensive functionality.

4. Multi-user screen sharing
Screen Sharing has been improved and now enables remote log-in to a separate account on another Mac.

Benefits include allowing IT admins to remotely troubleshoot problems and carry out upgrades without causing disruption. Business customers can also use the feature to work independently when using the same machine.

Screen Sharing still needs some tweaks, and browsing the web using the virtual desktop can be a bit ropey. But, for business users, it's good to know there is a tool available with which files on a Mac can be accessed in case there is an emergency.

   
5. Use the Apple Mac App Store
Although this has been out since January, the Mac App Store will prove a key feature for those using Apple's portable devices as they lack DVD drives. It's possible to get key software from the App Store, including vast numbers of productivity apps, and the importance of this store is only likely to increase as Apple puts more emphasis on cloud storage with the launch of iCloud.

 
6. Airdrop
This makes it possible to share files even when there is no Wi-Fi present.  A Mac will automatically locate any other AirDrop-capable device within 30 feet and allow an encrypted file transfer between them.

7. Resume
One thing that has always separated Macs from PCs is the impressive boot time. Apple has now added a 'Resume' feature which means that the Mac will automatically re-open all apps that were being used in the last session. This has been very useful as it allowed us to pick up right where we left off numerous times.

8. Autosave
Another invaluable feature that automatically saves files every five minutes, giving that extra piece of mind.

9. Mission Control
Among the noticeable visual tweaks are the Mission Control and Launchpad interfaces. Mission Control can be brought up by swiping three fingers upwards, and shows a bird's eye view of all applications being used on a particular desktop.

Windows from the same application are automatically grouped together, allowing you to keep track of what can otherwise become a crowded desktop. This is a great way of checking exactly what is running, particularly for those who may forget that they have left an app running in the background which they no longer need.

10. Launchpad
Apple has also brought the highly acclaimed iOS interface to the Mac for the first time. This shows applications in icon format, providing a quick way of accessing applications that are not stored in the dock.

It's possible to create folders, just like on the iPhone 4 or iPad 2, and anything downloaded from the Mac App Store will be located here.

When I reviewed Microsoft's Office 365 last week, I tested the cloud-based productivity suite on Windows PCs, running either Windows 7 or Windows XP.

To recap, Office 365 provides access to cloud-hosted versions of Exchange and SharePoint, plus Microsoft's Lync telephony client and web-based versions of Word, Excel, PowerPoint and OneNote.

However, with most of the capabilities of Office 365 provided through a browser, it should be possible for users on other platforms, such as Mac or Linux, to gain access to Office features.

To find out, I tried accessing my test account on an Apple iMac and a PC running Ubuntu with a version of Firefox.

The results were encouraging, everything looking and functioning exactly as it does when you access it from a PC. It would seem that Microsoft has done a pretty good job of ensuring cross-platform support via the browser, with this suite at least.

On both the Mac and Ubuntu I was able to access Outlook and send and receive email, check the calendar, and even edit shared documents stored on SharePoint using the Office Web Apps such as Word.

The one area where this falls down is with Lync, Microsoft's messaging and telephony tool. Unlike the other functions, this is a full-blown software client that must be installed locally, and non-Windows users are out of luck here.

While there is a version of Microsoft's Communicator (the old name for Lync) for Mac OS, Microsoft states on its Office 365 web site: "At this time Communicator for Mac 2011 will not work with Office 365."