The problem with the wonderswan emus out there is that the fast cores are all in x86 ASM. There is a slow, un-optimised, and (assuming no more work has been done on it since I spoke to Rattboi over a year ago) very dirty code-wise core in C++ (or maybe C... one of those two), but the quantity of optimisation needed is immense - and it ALL needs to be done on the core (ok... not all, but most); if you try WS32 (also based on Oswan) you'll find frameskip increases beyone 2 don't affect the speed - just the jutteryness.
If I remember correctly, yoyo's port of Oswan uses the same core.
Which basically means that without a LOT of work on the core and optimisation and such, the port isn't going to go anywhere...
As a side note, there have been several WS emus developed a little way - Rattboi's one (WS32), Ryleh's one, and yoyo's. They've all been held up by the same thing.
On a plus side, the WS actually uses an x86-based CPU (or so I'm told) so should an optimised core actually become available, then there's a possible starting point for - admittedly pretty slow - x86 emulation. Which would be cool.
