it matters to some extent. There are some variations in keystrokes - i.e. Mac uses a "command" button that doesn't exist on non-Mac keyboards (it's where the Start button is on Windows kb's). If you use keybaord shortcuts, as I and many others do, it's different. I don't know if using the Start button in place of command will work.
In general, to avoid annoyance I would go for a mac-specific keyboard. In terms of bluetooth and getting the basic handshake to work, that i don't have an answer for but would guess it probably works fine.