The 3DS is a fair bit more powerful than the PSP, so I'd hope it's possible - the Wii (from what I've read) is similar in power to the 3DS and can run an N64 emulator, so I'd hope it's possible...?
Off topic: GBAtemp really needs to add a sarcasm tag. Costello, take note.
Very poorly, I might add. But hey, there are always other system that could be emulated well - SNES, Mega Drive, NES, Master System, PlayStation, Game Boy Advance... N64? Not so much. The console is notorious for being hard to emulate not only because its hardware is a tad convoluted, but also because the games often used complex "programming tricks" to go beyond its limitations.
This is bad, now I have 5 friends calling me about this and word is going out to the public too fast. This means the 3ds will get patched soon

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How exactly do you expect them to patch something that's on retail cartridges in ways other than a System Update which you can easily decline? Besides, Nintendo doesn't know the nature of the exploit yet as it's not public.
...this would be a good time to stop updating your system just in case thought.

That said, we're at least a year away from proper libraries, so don't expect a homebrew fountain just yet.