Worms has always been a "Turn Based Strategy", both online and offline. I think it would be safe to say that this trait defines the series, and has been upheld through all generations of Worms, including the 3D ones, all the way up to this year's announcement of Worms Rumble, which is real-time (and therefore causing so much hubbub about its departure from the formula).

I haven't played W.M.D., but from what I've seen from the streams, pacing definitely feels different. The delays are a part of it, and they do subjectively seem less forced in Armageddon. For another thing, W.M.D. introduces crafting, giving players at least something to do between turns - in Armageddon you've nothing to do but follow the action and mock your opponents' mistakes :D