I've got the htc touch diamond (running wm6.1) and ubuntu intrepid v8.10 installed. Tethering and syncing worked out of the box.. no command lines, updates, upgrades, software installations necessary. Now if you're using ubuntu hardy v8.04 you can get your phone to sync w/ synce and tether using the method described on
http://forum.ppcgeeks.com/showthread...ethering+linux