Just read this via Major Nelson's Twitter feed:

In the booth. Just saw Perfect Dark on XBLA running 1080p. It is coming to XBLA this winter. Free theme coming tomorrow!

While I'm still bummed we probably will never get Goldeneye on XBLA, this news makes me happy. While it wasn't quite the multiplayer timesink that 007 was, Perfect Dark should still be a lot of fun to play online. I for one am definitely looking forward to some Laptop Gun carnage.