Just looking at schedules I'm not sure I could justify rooting for the 49ers.
Excluding this game against the saints, the only two threats on their schedule are the Rams and Seahawks and both of those games are at home. They play @Washington but the redskins aren't very impressive. Outside of that they play Tampa, Atlanta, and Arizona. I'd probably put there record in those games somewhere around 6-1 or 5-2, for a final record of 11-5. I honestly think we will beat them - there is no great home field advantage at candlestick, no reason to think we can't just play our style of football and beat them.
Saints schedule is not so favorable. They have to play the Panthers twice, Seattle, and @ the Rams who are apparently no joke and that close game against them suddenly doesn't look so bad. Their defense disarmed the colts. They play @atlanta and vs. tampa which should be wins but they are also division games. I see no less than 3 more losses for the Saints.
So in reality i don't see the 49ers or Saints (or lions for that matter) finishing any better than 12-4, while I can't fathom the Seahawks dropping more than two of their last 6 games and should finish no worse than 13-3.
Of course this is all moot if the Seahawks just do what they are fully capable of doing, and that is winning the rest of their games.