You dual wield with rogue because you get less of a backstab penalty. Typically you go SK epic main hand (it has 1H and a 2H version) with the offhand pierce from Inny I believe, since it has backstab mod on it.
You'll probably swap that out for Vulak dagger, but SK epic MH is probably BIS through Velious due to how useful the DoT tap is.
I'll have to start working towards that, appreciate the info! Going to get to 30 tonight and start burning some AA's, at least that seems to be the thing to do.