An emulator, such as SNES or MAME, is enabling a user to download a ROM (forgive me if I doubt most people's ability to dump a cartridge or arcade machine to linux/win32), copy to local disk (or USB), and play from there.
They are in effect equal in purpose and ability. Both have the purpose of allowing a user to play the game from local disk, and both have the ability to enable copyright infringement.
It's wonderful that you're waiting for an XBMC (or other) port, but that's not likely to happen. If you do want such a contraption, why not buy a Boxee? It comes with XBMC and is cheaper than a PS3.
Too many devices, you say? More consolidation, you say? Man up and put your equipment in your basement and run an HDMI cable through your walls to your TV. Get an RF-capable remote to control your devices down below.
I don't see the relevance. A backup manager, such as multiMAN, is enabling a user to backup his games to local disk (or USB) and play from there.