Hi, I have an iMac, MB and MBP all running 10.4.11 and syncing with .Mac. I haven't updated to Leopard yet because of all the problems I've read with 10.5 and since I've found 10.4.11 to be rock solid. Thought I'd give it a try with my MB after making a clone with SuperDuper. My concern is if my MB is running 10.5 and my other two Macs are running 10.4.11, will .Mac sync be affected? Will any settings like keychains etc be corrupted syncing back and forth with two different OS versions? Thanks in advance.