Glad to see I'm not the only one picking the show apart.

First what I liked;
"Are you going to eat my brain?" "That's disgusting!" Great shout out to all the internet speculators.

Also liked Matt thinking the tortoise was talking to him.
I'm over Sylar. Don't find him scary anymore BUT, if they are keeping him around, I do like that they seem to be trying to do something different with him.
What I didn't like;
Nikki was dead! She was gone! It was a done deal! I don't need to see her brought back as what is obviously the twin sister who was supposed to have died! People, meet the real Jessica.

Peter apparently gets really stupid in the future (must have absorbed some sort of lobotomy power) but what can you expect from a 30-something guy that chases teenage women. Oh wait, that's him in real life (icky!). Hard to follow that Peter's humble character would become arrogant enough to try and fiddle with time.
and where the Hell did he get that scar? Peter can heal! What happened? Did his whole face get ripped off?
Speaking of out of character, why would Hiro open the safe? His past actions would not seem to indicate that he was this childish ("I don't wanna be a sentinel! I wanna be a HERO!") and why didn't he just go back in time and get his father to switch the paper in the safe with a fake formula? Unlike Peter, Hiro was meticulous in his ealier time fiddling.
Also speaking of out of character, have you ever met a scientist that would be so foolhardy as to inject themself with an experiment with NO testing? It was reminding me of this movie I saw where a guy combines his DNA with a fly and gets all of these super fly powers... I think it was called... Spiderman.
So now Claire can't die. What the Hell happened to "Save the Cheerleader, save the world". I thought Sylar had killed her in that other timeline.