Is your iPhone taking forever to sync? I noticed that mine was taking a very long time. I let it sync overnight and it still was not done in the morning. I thought maybe it froze. This was not the case. I did a little more research and noticed that this is now a common problem. My issues was syncing my contacts. I began to read that iSync was causing the problem.
Make sure your iPhone is not syncing and then open iSync, go to preferences, and click Reset Sync History… This will also free up a lot of space occupied by the file Library/Application Support/SyncServices/Local/data.syncdb. If you are still having problems after that you can try to do a sync without your contacts in iTunes. After the sync finishes check your contacts back on and sync again.