The n64 emulator for android that the Ouya (and all other android devices - you can play smash on your android phone if you like) use is Mupen64plus. It's the best n64 emulator out there right now as it is completely cross-platform and works on Windows, Mac, and Linux (which is what Android runs in) and has very deterministic emulation (which means less desynch).
Ownasaurus and I had been talking about putting Kaillera in Mupen64plus, as the code is maintained well and the project would not be too difficult. The main challenge would be making a kailllera client that is cross platform and not dependent on Windows libraries if we wanted to have it working on all operating systems. Moving off kaillera, however, would probably be best.
However right now no work has been done. You can see here:
http://code.google.com/p/mupen64plu...Status Priority Stars Milestone Owner Summary
that netplay on mupen64plus has been talked about before. I posted in this thread over a year ago and it seems like there are not that many developers right now.
If anyone sees anybody doing work in this area, let me know as I'd be willing to assist in the development.