The primary reason is that I want a rematch against them. The Patriots went into Cincinnati during week 5 and played
Another reason I want to face the Bengals is because it means the Broncos will face either the Chiefs or the Colts. Seeing Peyton playing his former team or the Chiefs getting one more crack at the Broncos would be some quality football. Besides it's always hard to beat a team 3 times in a season and the Broncos have already played and beaten the Chiefs twice this year. Having the Chiefs take one from the Broncos and come to Foxboro for the AFC Championships would be great. It would give us another home game and be a matchup that I think favors the Patriots.
The final reason I want to face the Bengals is because it eliminates the Chargers from the playoff picture. The Chargers are pretty hot right now and are pretty well rounded. Being realistic, I'd like to have them eliminated from the picture as soon as possible.