I've never considered the SB to be the final determining factor in which team is the absolute best, too many fluky things can happen each week (hence "on any given sunday"). But I do think winning the SB is the most important thing for any fan, player or coach. Chargers fans in this thread seem to be suggesting that the rankings should shake out exactly according to how the playoffs ended. So by that standard, the best teams last year were, in this order:
Giants
Pats
Chargers
Packers
Colts
Cowboys
Seahawks
Jacksonville
Buccaneers
Redskins
Titans
Steelers
I don't think anyone would make that list if you asked them to rank last year's teams. As somebody said, the Rams were the best team in 2001, not the Pats, but that's what's fun about the NFL, the best team doesn't always win. And I don't give a lot of creedence to power rankings, but was there a single power ranking list that had the Giants above the Pats before last week? Who would Norv Turner say was the best team in the NFL last year if you asked him? Which team would the majority of head coaches rather have faced, the Pats or the Giants?
The confusion here, and it's led to inevitable trash-talking, is that you think saying the Pats were the best team last year is some kind of sour grapes rationalization, but I think it's merely a fair distinction. You won't find any sane Pats fans that wouldn't have traded 18-1 for the Giants SB win, but the Pats were the best team, and with Brady at the helm, they are still considered the best until something changes or another team rises up. But the Giants could not have possibly won 18 straight games last year, they were not good enough, and no other team could have either I don't think. That's not to say it's the greatest "accomplishment" but it accurately tells which team was the best. If anything, this is an even greater testament to the Giants accomplishment.
EDIT- That being said, injuries are part of the game and to say that the winner this year should have an asterisk or whatever is beyond ludicrous and unfair. Though I understand the backlash given the treatment the Pats have gotten and the character most other fans have shown in shamelessly celebrating Brady's injury. There is an element of fans being so desperate to beat the Pats that they'll be happy to beat them when their most important player isn't there, and I think that's pathetic.