The NES emulation discussion document has been updated (3rd release: September 6th, 2003). Besides having been practically rewritten, it now contains far more useful information in general regarding writing an NES emulator, with optimization suggestions being alot better as well. The most notable addition is that I stuck the MMX-example of the playfield renderer in there. It's been refined (it now contains the code to do the fine horizontal scrolling), and the comments should help explain better how it works. Since I've only sent the updated doc to Memblers today, have some patience if the doc hasn't been updated yet.