Apple - Cut-Paste files or folders on Mac OS X

The shortcuts to Cut and Paste files or folders in Lion (or later) are:

• Command-C to copy
• Command-Option-V to paste

While you can copy (Command + C) and paste (Command + V) files in OS X, the cut (Command + X) function is not supported. What you can do however is choose whether to Move, Copy, or Create an alias when dragging and dropping files.

• Command + Drag and Drop = Move File
• Option (alt) + Drag and Drop = Copy File
• Option + Command + Drag and Drop = Create Alias

As a side note, when working with files all on the same Volume/Partition Move is the default action, there is no need to hold the Command Key. Alternately, when working with files across two different Volume/Partitions, Copy is the default option and there is no need to hold the option key. You can always tell what is about to happen by taking a look at the curser before you drop. A green Plus (+) icon indicates that the file will be copied, the absence of this icon indicates a move.

If the Cut and Copy functionality is absolutely crucial to your workflow, then I suggest checking out OnMyCommand. It's a Unix and AppleScript Executor and if I recall, there are some user submitted scripts that will enable cut functionality for finder items.