I updated my iPhone to firmware 1.1.1. The upgrade took several minutes but was uneventful. I had previously restored it to the original firmware. Before that I had several third-party applications installed, although I never unlocked it since I don’t see any point in switching from AT&T. The only application I really miss is Apollo IM, although BeeJive is pretty good for AIM. I find that m.twitter.com is quite usable and has more features than Mobile Twitterific.