Unless you can kill every mob in 1-2 Touch of Chaos hits, Affliction is the best spec up to MoP. It's in MoP that it starts to trail off, since, without BOE blues, you can't kill mobs in a single set of dots. But, it's got about the same burst potential as Destro, so it's not going to be too bad if you spam Haunt enough.
"You're sorely underestimating the power of nostalgia goggles." - adjl http://www.smbc-comics.com/comics/20110218.gif