Over the past couple seasons, the San Francisco 49ers and Arizona Cardinals have combined for some solid matchups. Even when one of the two teams is streaking and the other is slumping, the familiarity between the two has kept the games close and interesting. The players know each other well, but there's some new wrinkles this season, mostly for the 49ers.
When the 49ers made the switch to Mike Singletary, the Cardinals still played the 49ers relatively close because, well, Singletary wasn't going to revamp anything when it comes to serious gameplanning. But now the 49ers have Jim Harbaugh, and for the Cardinals, this will be an entirely different team. Sure, they still have to cover Vernon Davis and Frank Gore will be the guy to bring down on every play, but the offense in particular functions so differently now.
In short, it's really hard to say whether or not much can be gained from recent years. The NFL really tried to get these two teams to cultivate some kind of rivalry over the last couple of years, but with the 49ers sitting with a five game lead in the NFC West, it's hard to imagine the teams really getting into it without the added significant of the division title up for grabs. With such different situations, a different coach for San Francisco and some new players here and there, it's not easy to draw any comparisons to the last couple seasons.
Regardless, the 49ers are favored in this game, as they should be. They're winning, beating really good teams, and generally looking like they're going to be the second seed in the NFC. The Cardinals aren't out of things yet, and will certainly be playing hard, so it's still a trap game. Just don't expect any budding rivalries from this one.