Still hasn't worked for me. I've got a new iPhone that's only been successfully synced once, and that was when I was setting everything up for it. After spending yesterday playing with the phone and running down the battery (which I subsequently charged using the AC adapter) I plugged it in but after about 30 mins I gave up and canceled the sync, and started searching on here and other places online. Funny that when I began typing the phrase "iphone takes a long time to sync" into Google that it came up with my exact wording as one of the suggested searches.
In terms of equipment, here is what I'm working with:
15 inch Macbook Pro (less than a year old)
Latest version of iTunes
iPhone 16 gb 3g with firmware 2.2
I've followed the steps that the OP has suggested, however I had no issue with warning screens popping up, then or now. Nothing has crashed on me since I got the phone almost 48 hours ago, therefore I shouldn't have any crash reports... right?
The syncing progress does not seem to be stuck on backup per se, I saw it flash "Backing up iPhone" for about 5 seconds then it came to what seems to take the longest: "Syncing contacts with <insert iPhone name here>..." I have 11 contacts on the phone, and a few podcasts. I have about 5 apps, all of them are free. I still haven't decided what music and videos I want to put on it so there is nothing in the "iPod" section of the phone.
Any other suggestions?