Before the flame war starts (I realize it's inevitable on this one), let me clarify what I mean by "true roleplaying": the game engine and "rules" place have as few restrictions as possible;. While most of the MMOs we play are allegedly roleplaying games, most of them define your role. A great roleplaying game lets you create your own role for yourself and act it out, similar to a character at an improv theatre. "Roleplaying" in most RPGs is sorta like being in Hamlet; you can put your own spin on it, but you're forced to working within the director's vision. Rosencrantz and Guildenstern? Great roles stuck in Hamlet.
Games like WoW can be considered "roleplaying," sure. WoW lets you become that burly dwarf that does a mean Gimli impression by gruffly saying, 'Where's the brew, mate?". But you're constrained by game limitations and people's expectations. For instance, if you wanted to role-play a "big bad dwarf that's a coward and wants to hide behind the priest's robes" well, that'd get old after the first instance and most likely ensure you aren't invited again. Yes, I know there's people like Naked Troll guy , but let's be fair, he's an exception in a game that derides people for not having the optimal spec on raids.