Why to watch
Could this be a divisional round playoff preview? What were the odds on that? These are two teams that have made huge strides this season and seem primed to be part of the playoff equation. There is just one combined loss between these teams, and that one loss could have easily been a San Francisco win.
Inside story
Alex Smith has been a turnover magnet at times in the past, and facing the Detroit pass rush on the road in that dome could bring some old bugaboos back. He's been extremely efficient with the ball in 2011. Do the 49ers have anyone who can match up with Megatron?