For gen fic, I think the biggest would be ignipes though recently she started doing some wincest too.

I'm not against any of it, though a story has to be pretty good for me to read it if it's slash. But I've been in plenty of slash oriented fandoms (highlander and sentinel come to mind) and never had such a problem finding good non slash fics to read. But I know part of it is I'm just not reading fanfic at least 3 hrs a day anymore probably as well.;)