Tested on Generation 2 MBA (Late 2010) and 2006 Mac Pro. Works fine. Seems to work like Snow Leopard did just with the new gestures etc. I did assign the F5 key I think it was to Launchpad as not having a button for it was pointless.
I am slowly getting used to the new gestures, I bought a trackpad for the Mac Pro, though there is one thing I don't like. Dashboard! I prefer how it come over the screen and was translucent. I use the calculator a lot and I often have numbers on the browser that I wish to refer to when using the calculator. Having to flick back and forth is annoying. I could probably find an app to do it but dashboard was perfect.
Oh well, can't win them all!