So I have Snow Leopard "Final GM" installed since yesterday (Friday) and I gotta say...there's not much to tell.
In fact, after installing and using it for a bit, I had to go into the "About Mac" option to really make sure I had installed it. I even had to visit the Apple Snow Leopard site to figure out what the heck changed.
Aside from a few visual effects in Finder, Quicklook, Stacks/Grids, etc. there's practically 0 noticeable difference. Mail and Safari open up quicker but it's like noticing the difference between Mach 1 and Mach 2 (you're already going fast so who cares?)
BTW, this was tested on a testbox MBA Rev. 2 1.86Ghz 2GB RAM, 120GB SSD.
In other words, you should be more excited about the Apple Tablet than Snow Leopard.
But if you're overly excited for SL, trust me, your expectations will be severally crushed after installing it. It's practically the same Leopard we all have today.
Sorry guys. :-(