the "hunger" is not just a need to slice open people's heads. He slices open those heads because after looking at their brains he can supposedly see what is different, how their brain works to give them the powers that they have. How he makes that change in his own brain is anyone's guess but you have to stop taking everything so literally.

The thing is, Peter already had the power to get people's powers, and keep them, didn't he? At the beginning of the series, he would lose heroe's powers when he moved away from them, but didn't he learn to keep their powers? Isn't that how he can shoot people with energy balls now? Why the fuck did he need good Sylar anyhow?

[Sorry for the language, but Heroes just makes no sense whatsoever. Lost at least keeps internal consistency with its own logic, most of the time]

I must rewatch the episode because I totally missed that. WOW! I must have dozed off for a few seconds (I did watch the episode after midnight).

I thought exactly the same thing until now, when I read the above comment, to think about why Peter needed "Good" Sylar to teach him the power. I think it's because it's not REALLY a "power", just a desire to understand things. That's how, I think, Sylar got his first power, but understanding it, and THEN became a super person.