Just a couple of numbers short of Pi, Apple have released iPhone OS 3.1.2 which fixes the (quite frankly) horrible bugs that crept in with the 3.1 update. I've been suffering from the wake-from-sleep mode hanging the connection, as well as the odd delays and jitter (not to mention random menubar-sized gaps at the top of some screens). Given that 3.1 has been the buggiest release so far in terms of usability, I'm really hoping that 3.1.2 fixes all of these problems, and that I can update in peace. I'll update this post once I've updated and used it for a few days to confirm whether it does, in fact, behave as it should afterwards.
Links to downloads: