Hmm, Sylar has the urge to get new powers, yet he didn't look at Mr.P's brain to get his shit ton of powers.
Yeah, if you have something lodged in your brain and you're a healer then you're "temporarily dead". The bullet could be removed, like they did with Noah and I think Sylar, or like in Season 1 when Claire had that stick jammed in her brain. But Sylar said that "Claire was special" and he couldn't kill her if he wanted to, I'm thinking that the reason she was special and couldn't be permanently killed was because she had the catalyst inside her. Now that Mr.P has the catalyst, he could be the same way you know.
panda: Yeah, there was a scene like what dragonx said, the elevator one was really out of character for him though. Killed 4 people (three of which didn't have powers) in a office, then rides on an elevator with hands covered in blood next to a scared Asian guy, and doesn't kill him. just can't kill the asians.