I personally think Anakin using force lightning is a little over the top.
However, ign.com posted some screen shots of the Ep III video game. In a shot of the duel with Obi-wan Anakin is definately blasting his former master with lightning....then again, he's also holding a purpleish lightsaber, so the game is no guarantee of movie events.
I think he'll use it. Although he won't use it in the manner I want him to (against Padme...makes more sense for her to have the death from that than a Force Choke, and you could say that he doesn't use Force Lightning in the original trilogy cause its too painful seeing Padme shocked everytime he uses it. That would help explain the end of ROTJ too but, no, don't listen to me Lucas, lol.) But yeah, I think he'll use it, if not just for a moment.