OzExige
macrumors 6502
I think Leopard would be best for you. It's not running so amazingly on my PowerBook. I love the new features and UI. I run leopard on all macs now. It's a lot nicer. You have a nice new intel mac, go for it.
10.5.3 is crappola, I'm STILL in huge amounts of grief waiting for my extreme to reboot!
This is my third day of sitting up most of the night running disc utility and restarting the MBP.
Please mother of God help me.