Sony, but I don't know if it's in general, or just because the same group of anti-Sony people seem to show up in every single thread dealing with anything Sony. A few have posted already and I expect a few more, eager to tell us how Sony has earned their hatred. Does Nintendo also have a dedicated group of haters here as well?
There are also some members, aligned with both Sony and Nintendo, that are so hyper-defensive about ANY criticism that it can be hard to keep threads from dissolving into puddles of pure malice. A few of them turn their hyper-defensiveness into aggression by openly and childishly wanting other consoles to fail, which just sickens me.
All told, however, more of the Microsoft crowd hate Sony for some reason, so I think that gives Sony the hatred lead.