UK here..the only advice I could give is don't buy it..
in fairness it depends whether you want a great phone with some multimedia use or basically an iPod with the phone bit tacked on and not very good.
so to answer your questions..
1/ No
2/ O2 3G service in my experience is awful everywhere but major city centres. The iPhone in the UK struggles to keep any sort of signal in 'weaker' areas where a cheap Nokia candy bar is fine for calls and texts.
3/ Camera is awful, you need to do the COD4, hold breath move to get any focus.
4/ Not that I'm aware of.
5/ GPS varies from spot on to wrong continent...honestly!
6/ Possibly
7/ No idea
8/ No, just a mess of majority rubbish with the occasional gem in there. Lots of ads in the free apps too. Lots look cool and then you realise there are a bit pointless.
UK here, and my advice is ignore the above.
1) Depends. Do you have < 8GB of stuff you want to store?
2) O2's data coverage is hit/miss. You'll most likely find shoddy 3G performance anywhere outside of major city centers. Their 1G coverage (i.e calls and SMS) is, in my experience, pretty average. Not the best of the carriers, but not the worst either. One quick note: forget about EDGE coverage. It's virtually non-existent.
3) What do you expect... It's a mobile phone camera. It won't take good photos, but for the occasional snap it's fine.
4) Yes there is a limit, but unless you're tethering and/or trying to hit the cap, you won't. Soft cap is somewhere > 1GB IIRC -- but again, you just won't hit this via your phone, even with heavy daily use. (I use about 100MB a month, and that's with constant e-mailing and browsing.)
5) Yes. If you've got a GPS signal, it'll provide good accuracy. The more satellites it can lock onto, the better the resolution. With a 5+ satellite fix (not uncommon when in the clear), you'll get a fix accurate to several meters. If you can't get a GPS signal, however, (i.e. if you have to use cell towers to estimate position) accuracy varies wildly.
6) No idea.
7) Same.
8) Yes, although I haven't used it much. I use Shazaam for music identification, and I've played a couple games, but most of the software I use is either stock software or *nix utils obtained via Cydia.
