I have recently started using Snow Leopard and besides having to recompile an Applescript app, things have been going good. One big bug that I have noticed is that when I’m logged in as an Active Directory user, Software Update doesn’t work. It seems to hang after you press the Install button. There is a simple workaround though. Login as a local Admin and run SU from there. Seems to be just a bug but I’m surprised Apple hasn’t resolved it by now.