I'll start with the division I know the best.
Pittsburgh Steelers: Very highly favored already. Not much has changed, lost the RT, but he wasn't the greatest... lost the RG, but Kendall Simmons, who is the real starter, was injured last year and is back, so no loss here. The secondary is surprisingly young, and the rest of the D is the same as last year. LeBeau is still in charge of the defense, Roethlisburger has a year under his belt. Staley will be running well like he did early last year (when they were winning by blowouts). Should have no problem rolling into the postseason.
Cincinnati Bengals: If the Bengals defense solidifies into a good unit, they could be the Chargers of last year. Real cinderella possibility here. Carson Palmer showed at the end of last season that he is the Bengals QB of the future... Rudi Johnson is a good workhorse. It all lies in the defense. The DT position was corrected via the draft, so we'll see how it goes. Remember, Marvin Lewis is a defensive guru, so he does have the capability of creating solid Ds.
Baltimore Ravens: Baltimore has a few disadvantages, and I think this year will really show them. They brought in serious talent for the offense, but the offense is still running under their biggest problem... Kyle Boller. This should be his last year. He has shown flashes like twice in his few years in the big leagues, and it was against poor defensive opponents. Rex Ryan (new DC) will put some flavor into an already strong defensive unit, but I'm starting to think that the defense is showing its age. Ray Lewis, for example, should have been tossed in favor of the younger Ed Hartwell. This defense isn't Ray's anymore, it's Ed Reeds.
Cleveland Browns: Sorry Brownies fans. You got another year of rebuilding. So far, I've seen Savage and Crennel really work their magic on the team. The only two big problems I see are: Kellen Winslow Jr being an idiot, but you can chalk that up to a "Butch Davis" blunder, and why in THE hell did they bring in Reuben "product of the denver RB factory" Drones? The guy was a FB for Denver for years, is plugged into the system for a reliable player, and Cleveland brings him in and pays him starting money. Folks, I could have a 3 yard per carry average if I was the starting RB for Denver. Drones will be just like Olandis Gary... good in Denver, bad elsewhere. Should just stick with Suggs and give Green another shot. Braylon Edwards is a good pickup and the new DC (form DL coach in Houston) should really make things happen. But you have to wait one more year, Brownies (though if Kyle Boller REALLY fowls it up, you could get #3). Oh, I also LOVE the pickup of Trent Dilfer to keep the seat warm for Charlie Fry. Dilfer won't win ya games, but he is pretty good at not losing them. He'll be a great mentor for the youngin and will make sure games aren't lost in the passing attack.