I just updated to iOS4 on my iPhone 3G. I've had some major issues... First off, anytime I tried to restore from a backup, it would get stuck in a boot loop. I had to start from scratch again. Second, It crashes randomly when I try to sync, use it for a while, or when it auto-sleeps. Thirdly, none of my contacts will pull down from MobileMe; everything else will, mail contacts etc. Anyone have a solution for any of these problems? Luckily my iPhone 4 is coming in on thursday and I only have to deal with this for a couple of more days.