Sync iPhone with multiple Macs

Solution 1:

The best way to synchronize contacts and bookmarks between several Mac and/or iPhone is to use MobileMe (now iCloud). It will sync all as you need where you want.

Solution 2:

You actually don't have to buy MobileMe to sync contacts and calendar to multiple Macs and multiple iOS devices. This can be accomplished with only a free Google account. If you want more details on how to set it up, please ask.

As far as I know, there is no way to sync bookmarks without MobileMe.

Solution 3:

Actually, I just answered the question to how to keep your device's music library synchronized with 2 machines as well: Sync iTunes U between 2 Macs via an iPod