I've had my iPhone for about a week now and here's my impression of it, as someone who's previously had a Blackberry and before that one of the nicer business Nokia:
Display – excellent, much better than any other phone I've used for both clarity and size
Keypad – very god for a touch screen and much better for mail etc. than a normal phone keypad (e.g. like my E51) however it's not as good as the keypad on the Blackberry Bold I had.
Email – Very good for reading and responding to email, pretty much up there with the Blackberry
Apps – some fun games and some useful apps available
GPS – not convinced how useful this is in reality, partly because it doesn't seem that reliable but mostly because of the limited battery life
Battery – terrible, perhaps no more than 4 hours if I run the phone they way I would my Blackberry (I was getting 3-4 days with that). I'll give turning loads of stuff off a go, however for someone who's out and about a lot in meetings etc. that does seem to remove a lot of the reasons you'd get an iPhone in the first place. I could buy extra batteries etc. to carry around but the iPhone is already pretty bulky so I might just carry one of my old phones as a back-up instead.
