Lion: Cut and Paste in Finder
Lion adds a “new” feature where it moves files by copying and then “pasting” them. When you hold down ⌥ while having the Edit menu activated the Paste entry changes to Move Item Here.
So to Cut and Paste in Finder you just have to remember the pasting bit, as opposed to the “first cutting out” bit like on Windows.
via TidBITS Macs and Mac OS X: Our Favorite Hidden Features in Mac OS X Lion