Lion multitouch and older intel Macs
I can confirm that Macs without the newer multi-touch trackpads (or an appropriate mouse) only have limited gesture support on Lion. I have a late 2006 Mac Book Pro with an early multitouch trackpad. It basically supports two finger touch but not three, so a lot of the Lion gestures are out.
I must say I’m still getting used to “natural”(!) scrolling. Great on an iPad, feels weird on a trackpad. Perhaps it’s just and adjustment period.