It is disabled, you have to manually enable it via the Terminal.
The cut/paste in Lion people are talking about isn't technically cut/paste. You copy the file (cmd-c) and then use the Move Here command (cmd-opt-v) which moves the file instead of copying it, removing it from its original location. It's essentially cut/paste, but not listed as cut/paste in the OS menus.
This seems a far better implementation to me. I never understood the cut/paste mentality to move files. In all other instances, cut removes the item being cut, deleting it if something else is copied/cut over it. Why does it act differently just because it's a file? Yes, I realize it's so you don't accidentally delete files, but the usage is inconsistent.