I've been watching, just been a little too busy to keep up with this thread.
I'm not sure why Peter doesn't have his scar. It could be a number of things -- he met up with Claire at some point shortly after getting the scar, got her powers, and healed; the previously scarred Peter we saw from the future got his scar another way before meeting Claire for the first time and that scar was permanent, and this one wasn't severe enough; Peter hasn't received the permanent scar yet; the producers are trying to save money on makeup.
I like that he has to touch people to get their powers, though. As he was he seemed TOO powerful and he and Sylar were almost redundant. Hopefully the powers will be permanent. The temporary thing would make him TOO much like Rogue from X-Men; besides, Sylar does need a heavy hitter who can counter him. Yeah, I know I contradicted myself there. I still think using his powers one at a time would be a good limitation to keep Peter from being too powerful. The fact that he was holding on after the plane opened may mean the powers are temporary and he couldn't fly. Or he didn't want to leave Claire and the others and wanted to try and save them (typical Peter).
Nathan is a real (insert any filterable word here), isn't he? He probably has some delusion that he and only he can control those with powers, that he will be a great leader and bring them together to be a force for change. Yeah, depend on those you kidnapped to be your army. Real smooth move. As it is, he's going to face challenges from two fronts -- Peter, Claire, and their allies, and Sylar.
One things for sure -- this season will see more action.