Judging from Alternate Future Peter, I think Peter did get Sylar's abilities. And I'm fairly certain that Peter has picked up or will soon pick up almost every other Hero's powers. Which would make him, essentially, a god, wouldn't it.
I know Sylar will die, but I don't know if it will be by Hiro. Sylar will be in Season Two as a regular. But regardless of when he does die, I wonder how much the future will change, since he doesn't explode? Then again -- oooh, new theory -- if Peter does explode, would there be a way to create a telekinetic force field containing the blast?