Ok, so I have an iPhone 3G, a MacBook, and the most up to date version of iTunes 8. This problem just started today. iTunes runs fine until I plug in my iPhone. The second I do so, it says "Syncing iPhone" at the top of iTunes, and then iTunes freezes and the sync never gets any further. I tried searching the discussion boards and haven't found any solutions yet. I've tried reinstalling iTunes, and that didn't work. Can anyone help me out?!
Same problem here - the syncing problem just gets worse & worse on the iPhone 3G. The only thing I can think of that has changed recently is the recent Security Update which I just installed yesterday. Even though I've always unchecked the automatic sync box it attempts some kind of sync every time I plug the phone in (I've just unchecked every kind of sync possible - contacts, calendars, photos, podcasts etc - which seems a bit extreme just to get iTunes not to slow down and freeze up with an iPhone plugged in). This time I just left iTunes for about 30 minutes when it froze up for the millionth time - this time it eventually unfroze itself and complete whatever it was it was trying to sync - a ridiculous and unacceptable amount of time IMO. I detest the whole sync process and much preferred the iPod and iTunes when it was a simple drag and drop set-up.
I solved my problem by going to itunes/preferences/devices and deleting the back up for my phone. I then did a sync and now everything seems to be working as it should.