1. In Snow Leopard, 4 fingers up pushes windows out of the way on the desktop. In Lion, this is a reverse pinch motion with 4 fingers and it is not reliable. Three fingers up and four fingers up do the same thing in Lion, so there is no reason they couldn't offer alternative motions, rather than pinching...
2. Try this... Push upwards with 4 fingers in snow leopard, but do not remove your fingers from the touchpad. When you pull them off a few seconds later, the windows will return.
If you push up without hold, it will wait for another push up OR push down motion before returning. Snow leopards implementation of the motions is trivial.
In Lion, the push and hold as well as the ability to repeat the same motion to return to the previous state is gone.
3. Remove the 4-finger pinch motions. They suck.