That won't happen until at least the end of next season. Brett signed a 2 year contract with Minnesota. I think it's something like $25M bucks for 2 years. He gets $12M this year and $13M next year. Besides that, Minnesota is the only team, other than the Buffalo Bills, that have made it to the Super Bowl and not won it all.
Of course, Buffalo did it 4 years in a row.Thank God the Vikings had the decency to spread their humiliation out over the course of 20 odd years.....
EDIT: Also, don't forget the fact that if the Vikings do go all the way this year Brett will be getting all kinds of incentives and bonuses added to his already ridiculous contract and might want to tack on a 3rd year to his "playing retirement". Sheesh, he reminds me of Michael Jordan. If you're going to retire, at least do it with some dignity. If you're walking away from the game for good, DO IT! All this wishy washy BS just makes you look like a fool that can't let go of childish dreams. Hell, he's already won a Super Bowl, what more does he want, egg in his beer?