The browser wars continue to rage, and Mozilla's latest iteration of Firefox introduces a slew of new features and improvements to up the ante.

Probably the most noticeable addition in Firefox 3.5 is the inclusion of Private Mode, a feature already available in most of today's popular browsers - it's called Incognito in Google Chrome and InPrivate Browsing in Microsoft's Internet Explorer 8. The feature allows users to surf the internet with a greater degree of anonymity as no local data from the session, including history, cache files, form data, passwords or searches, is kept on the machine.

Private Mode can be activated from the Tools menu. It closes all existing windows and begins the new Private session with a clean slate. Once the Private Mode is stopped the previous session and all its tabs are automatically restored. While this removes any confusion about what is running under Private Mode and what is not, it can be frustrating if you need any information from a previous window when entering Private Mode.

Users also now have a lot more control over data that has already been stored locally, as it is now possible to clear recent history from the past hour, two hours, four hours or day, as well as erasing all history as per normal. Similarly, from the history library users can also opt to 'forget about this site' and remove all reference to a particular site. It should be noted that sub-domains are not affected, so 'forgetting' about maps.google.com, for example, won't affect anything from mail.google.com.

Mozilla has also done a lot of work on tab management with Firefox 3.5, making it easier to sort tabs. This includes a new feature called 'Tab Tearing' whereby users can reorder tabs within a window, and move them between windows as well. 'Tearing off' a tab and dropping it on the desktop will cause it to be opened in its own window, while if the last remaining tab in a window is moved to another, the empty window will automatically close.

Firefox 3.5 includes location awareness, allowing different online services to find your location based on information about your internet connection. The system uses any information to hand to pinpoint your whereabouts, be it your IP address, nearby Wi-Fi signal information and 3G data if it is available. The results will vary depending on the connection. For instance, someone on a 3G data connection will get their location pinpointed quite accurately, while someone on a wired local area network connection connected to a larger company wide area network will get only a very rough estimate. In general, we found it got a location down to within a few blocks, which should be accurate enough for most location-based services.

Although this feature will be of limited use to desktop PC users, it could be very handy to laptop users and will be ported into mobile versions of Firefox such as Fen nec where it could prove a lot more useful.