Extremely long sync time iPhone 3G

Does it take 7 hours to back-up the phone?
Or does it say sync in progress or syncing ihogs iphone for 7 hours?
If the backup is taking 7 hours, I would start by removing any and all photos from your phone. If that does not improve the backup time, I would remove any and all applications from your phone (as application data is stored in the backup) and attempt again. If that still does not remedy the situation, I would restore the phone.
MB985LL/A Mac OS X (10.6.1)

If it is backup time that is taking so long it is almost a certainty that the problem is an added app if it happens more than once. Photos can cause a slow backup once, but if you dont add photos the photo backup wont be repeated.
The most common app that can make backups take forever is Facebook. If you have the Facebook app on the phone try deleting it and sync again. If that fixes it you can reinstall Facebook, but delete it whenever your backups get too long again.
If it is the whole process and not the backup perhaps you are connected to a USB 1.1 port instead of USB 2.
Lenovo T-60, Intel iMac , Dell/Ubuntu 8, iPhone 3GS 3.1 Windows XP Pro Leopard 10.5.4

The phone shows Sync in Progress and iTunes shows Backing up iPhone.
Its connected to the iMac w/ a USB2.0 hub.
intel 2.16 Imac Mac OS X (10.6.2)