These are my ongoing speculations and theories about characters in the tv show.
He can do more than absorb powers. He's an empath, and absorbing powers is only part of what that means. He absorbs how people feel. When he was in the hospital, as he exited, he succumbed to the sickness that had been around him. Why it hadn't affected him before then might have to do with The Haitian, or something else, but when he got sick it was his empathy for those suffering that overwhelmed him - that almost killed him. It's impossible to predict what else he can absorb.
The death of Eden McCain was sudden and brutal, and went exactly as Sylar had wanted. Only, it was too perfect. For a woman who has the ability to suggest anything to anyone, you would think she could have come up with something better. But what if she did? What if what we saw was what Sylar experienced, but she actually only suggested to him that's what he saw? That he only thinks he killed her? What if Eden made a similar suggestion to HRG only moments before? That she told Mr. Bennet what she wanted him to believe their conversation was about, and that when next they met he'd think she was dead? Then she'd tell Bennet when he found her allegedly dead body that he had already called the ambulance and had the room fixed and Sylar put away, but none of that ever happened? She only told him what she wanted him to believe. Because after six months, Eden realized the only way she would escape both Sylar and Bennet, was if they both thought she was already dead.
Early in the season, Micah could tell nearly at a glance when it was Niki and when it was Jess. The writers currently have conveniently ignored this fact for plotting purposes. They explained it off as Niki putting makeup on her shoulder to hide the tattoo, as if that was what made Micah and DL know. Micah was able to see through Jess because he knows his mom. One can buy that D.L. might be fooled, but not Niki's own flesh and blood. D.L., God love'm, is at times dim as a lightpost with a broken socket. Of the three of them, Micah has proven himself to be the most intelligent. An alternative solution would be to somehow explain later that Micah knew it was Jess after the asylum the whole time, but has some motivation for not bringing this up. For example, he doesn't wanna get backhanded again like the last time. Or maybe he actually likes Jess cuz she's not as whiny and annoying as his Mom. Something, but instead I predict the writers will continue to ignore this established fact from earlier in the season that Micah can tell his Mom apart from his dead auntie, and this will weaken the validity and appeal of the Sanders' family in this storyline.
Mr. Bennet's power, if he has one, is a power that wouldn't necessarily give on an edge in overpowering an enemy. It's not an offensive power. It's not an ability that one can glean by the means Sylar's had to see other people's powers. In our experience, Sylar's had to see the power in action before he can actually take it. He can't sense someone has power, but once he knows someone has a power, he knows how to 'fix' it. Sylar can't get Bennet's power by cutting him open. In Bennet's case it just doesn't work that way. Bennet didn't get his power the same way the other principals got theirs. In fact he's probably had this 'power' for a long time. A very long time. At least long enough to have made those glasses of his fashionable when he first started wearing them. It's not genetic - he is a living curse of fate. Bennet's power also makes him a kindred spirit to Claire. It's why he is so hellbent on protecting her, because he sees her as like himself, perhaps after a very long time of searching for someone like himself. Though she's not his biological daughter, he feels she's more like him than any other person on Earth. Of all the powers in the world, her power potentially makes her the most like him that he has found. He's very centered on the concept of family, but he can't actually have a family. He has to fabricate one and create the illusion of family. Perpetuating that illusion at all costs is very precious to him. Sylar didn't kill Bennet, because nothing kills Bennet. Nothing can. This isn't an evolutionary thing. It's not something Bennet can explain. In fact he's probably tried to kill himself, and the end result was that fate won't let him die. Bennet's power is immortality. By "Company Man" we'll find out whether or not I'm right.
It will be revealed before the end of the season that Mister Muggles is actually an enhanced human whose ability is to change into any breed of domesticated dog. He will have been an old flame of Sandra Bennet's and when she married Mr. Bennet, he became her pet so he could be close to her. When he's found out, he'll be shunned from the Bennet's home and have to find a home elsewhere. Eventually he'll be found as a 'stray' by Micah, and spend a couple seasons in the Sanders' household, until Jessica "accidently" slams his head up against the wall with a baseball bat.