One of the things we missed most in moving from Snow Leopard to Lion was the cartesian layout for Spaces. For a couple of weeks we've been using a tool called TotalSpaces that brings this back, and so far it's worked really well.

TotalSpaces is an inexpensive add-on for OS X Lion and Mountain Lion that brings back Snow Leopard-style cartesian Spaces. It also makes it easy to disable the transition animation when moving between spaces.