With this new exploit coming, I was just thinking about all the possibilities. What might be in store for us?
Im guessing it will be able to unlock alot more power to run N64 games better. That would be awesome by itself....
But what about PS2, Saturn, and Dreamcast stuff? Would Vitas full power be able to handle such stuff?
The PSP and Vita are complete different system architectures and until there is an official-unofficial SDK for the Vita there won't be any homebrew/emulators.
It's why Yifanlu made that post with all of the documents on the elf format and how Vita binaries are signed etc. As far as I can tell, he wants this to be the Vita's NinjHax(although don't assume it will be as succesful as the 3DS, we don't know anything yet

)
As far as emulation goes:
I'd say PS2 would run extremely slow if it ran at all, same for GC/Wii.
I think 3DS emulation would be the newest console emulation possible that could be playable.
The 3DS and Vita have the same CPU architecture which will make emulation so much quicker(could natively run some of the code) and Vita has most of the Controls for the 3DS.
It could run very well, or could end up being the equivalent of the psp's DaedalusX64 for Vita.
What would hold these up most of all would be developer interest, there are a lot of people who would love to have these systems on their Vita, but all of these emulators would have to be re-written for the Vita(or atleast most of them would) and I don't know if anyone would want to considering once all that work is done they don't run well.
Oh, and N64/PSX and older are definitely possible.
Also, here is the
current progress on the vita toolchain.
Edit: Sorry, yeah Dreamcast is definitely possible, and it would most likely be playable(50+fps).