Well, define gameplay. I mean, for the sort of story-telling style Bioware does (and for some reason never wants to fundamentally change), you don't need different gameplay. NWN stuff worked fairly fine, so there's no need for them to treat new waters there. Not that I say that is how it should always be, but the NWN-style gameplay is the least thing that bothers me about DA.
Still, Bioware ought to come up with fundamentally (no, not revolutionary) different stuff. I mean, don't they have the urge to make something different for a change?
Bioware can keep their RTwP combat system all they want. It worked pretty well in BG1/2. The problem is, regardless of what type of combat system they've been trying for since then (NWN, KOTOR, JE, ME), they've all been dumbed-down drivel.