For what it is worth, I’ve been running Snow Leoaprd through the last few builds. It just feels SNAPPIER™.
The net effect for most people will be the same as a point update coupled with a faster machine. A real deal for $25.
I don’t think we are going to see the true benefit of Apple’s two years of work for another few months when new hardware is released.
Here are other slightly longer and more thought out reviews: