Andy,
First, for me personally, IBBIT. For me, Bill Walsh and Bill Belichick are the only 2 NFL coaches I've seen who truly deserve the "genius" label so often applied. They stand apart for their innovative schemes (offense for Walsh, defense for Belchick), HC ability, game management, personnel management, general manager capability, and ability to sustain it over the long haul. Bill Parcells is probably the only other guy around who can even make a claim to being able to excel at all those things.
That's not to say BB isn't fallible. Some of the most exceptional people I've ever worked with are prone to ego and judgment issues, and I'm sure BB would be the first to admit that he's made some mistakes. That's fine. He's made fewer than most, and more than enough brilliant moves to make up for it.
As far as I look at it, we ended the season with legitimate SB contenders in 2001, 2003, 2004, 2006 and 2007. The 2002 and 2005 teams had major flaws. 2008 might well have been a contender but for TB's injury, though I question whether our porous secondary would have held up in the postseason. With 4 SB appearances and 3 wins, that's far better than anyone else can claim.
My biggest concern right now is that I believe that we have the talent to legitimately compete this year, but I don't believe that the style we are playing will allow us to be competitive if we continue the way we have started. It's more than just being rusty on offense and young/injured on defense. We just can't throw the ball 50 times a game and expect opposing defenses not to adjust. We can't just play a soft defensive scheme allowing average QBs to rack up 100+ ratings and expect to shut anyone down. Not to mention that we're kind of boring and predictable right now, and not much fun to watch.
I don't expect anyone to be harder on how the Pats' have played (and have been coached) so far than BB. I still think we have the best HC in football, by far. But I would feel much better if we had an experienced OC and a DC in whom I had confidence.
We will get better, without question. Will it be good enough? That's a different question. It's still too early to tell. We have the talent to be good enough, but that may not be sufficient.