Apple may not have made the major hardware upgrades to the iPhone 4S that some fans were waiting for, but Cupertino has introduced some very interesting and useful software that shows just how far artificial intelligence has come.

We're talking about the Siri 'personal assistant', which is able to understand natural speech and come up with a response to pretty much any question you can think of.

From demos circulating the web we expected Siri to be a softly spoken American chick and were disappointed to find that as UK users we were lumped with a rather snooty sounding English gentlemen.

We managed to ditch him for the softer tones of the American lady, though, by changing the language settings to US English. We did have to start speaking with a slight American twang for our speech to be recognised, but the female version of Siri is far less irritating and worth switching to.

We also experimented with Australian English and were greeted by an equally likable Sheila answering our queries.

In terms of actual speech recognition, Siri is very impressive. The software is able to compute questions in microseconds and deliver answers almost instantaneously.

Really useful business features also include the ability to dictate emails and text messages as well as set appointments and reminders.

When configuring the latter two, it really is like having a conversation with a personal assistant as Siri asks "when is your appointment?" and "what time?" before confirming the details and activating a reminder.

Unfortunately, in the UK it is not possible for Siri to provide maps, directions or suggestions for locations such as restaurants as Apple has not yet signed a deal with any local information firm, like Yell in the US. It can surely only a matter of time before this feature is made available in the UK, though.

In terms of factual answers, Siri sources information from Wolfram Alpha, Google, Bing Answers and Cambridge-based firm True Knowledge. No Wikipedia in sight - perhaps Apple don't consider it accurate enough.

We also asked Siri some fun questions just to see the responses. Of course answers may vary, but we received the following smart aleck replies:

V3 : "Which is the best smartphone?"
Siri: "There are other smartphones?"

V3: "What is your favourite colour?"
Siri: "My favourite colour is well, I don't know how to say it in your language. It's sort of greenish, but with more dimensions."

V3: "Do you like Samsung?"
Siri: "I really have no opinion."

Finally, we got a rather creepy response when we asked Siri if it was self aware. "No comment", is not the answer we were looking for.

Siri's database will continue to grow and its usefulness will no doubt increase as Apple continues to amass more partners. It's also likely to spawn many copycat pieces of software, just the same as the iPad led to a slew of imitation devices being launched.