Got my 3GS 32 GB phone, seems they had some in stock in one of their stores in Sydney. Compared to the old 2G phones this thing is a work of art. The GPS could use an external antenna, but with the tower assist it seems to get my general location correct. The integration between hardware and software is just magnificent. Things just work.
I jailbroke it of course, inspite of Apple's 27/7/09 email that says we risk bringing on the apocalypse if we do. Hmmm, I hear horses, sounds like four of them.... Anyway, the view into the system through SSH or Fugu is instructive, they've modified OS X a bit and some things just aren't there, sudo, for example. It appears that the iPhone is running everything as root, which might explain why they locked it in the first place.
One thing I don't like is when I loaded some free apps on it and then tried to sync those apps to another computer it deleted them. And the first computer I sync'ed it to had American dates set up and it changed the whole system to American, backwards dates, spaces in the wrong place in phone numbers, etc. And there doesn't appear to be a full system preferences in the phone. Changing the computer to Oz settings and resync'ing fixed it.
After the horrors of Windows Mobile (I had a 16 GB sim card in an HTC Kaiser) and it's constant running out of system memory (no one needs more that 128 Meg of system ram), this phone is a joy to use.
The iPhone does monitor data so I just need to reset the counter every month, but I doubt I'll use 5 GB. The other thing I notice is that when the phone drops into 2G the browser is horribly slow, it's almost like being on dialup!