There are new features in Snow Leopard, and you might already have seen all of them in other blogs..
These nes have been pretty hard to find:

1st Snow Leopard is 64 bits. But not all of it…
When you boot in Snow Leopard, for some compatibility issues (“old” intel macs) it boots in 32bits and only after that loading snow itself switches to 64bits.
so if you whant to enable “complete” 64bits, have a look at this small app:
Startup Mode Selector (you can download there)
It worked perfectly for me, and also boosted my boot!!

2nd trick is about a new feature in the dock:
you can now minimize the windows directly in their own dock icon.
To enable the feature you just have to see in Dock Preferences and check like show below:
I love having my screen all tidy up!!