According to ESPN (televised...here's the link just posted) Brett Favre sent an e-mail verifying that he's calling it a career after one year with the Jets.
I'm sure that we'll be hearing more than a few puff pieces about Favre over the next few days and weeks, so I'm going to go against the grain and sum up my opinion of Favre's retirement in two words.
Frankly, it's a retirement probably way overdue for one of the most overrated quarterbacks in NFL history. Granted, Favre holds many of the major passing records and statistically he was a great QB. But my own opinion is that Favre's career as a great QB basically ended the year that Mike Holmgren bolted from Green Bay to take the reins in Seattle. Since that point, Favre has more often taken his team out of big games than won them and he's stopped at nothing to throw any coach, GM, or player under the bus who dared to shake up the special treatment he felt he was entitled to.
Just check the stats, if you don't believe me...from the 1999 season (his first without Holmgren) on he wasn't the same QB that came before, especially in the playoffs (and especially in cold weather). Not too many QBs get to keep their jobs after a 4 INT game in the playoffs (2005 wild card), much less a 6 INT game (2002 Divisional round). You didn't see anything resembling that when Holmgren was his head coach. The 2008 NFC Championship game (where he tossed an indefensible game-losing INT in overtime) was just the culmination of 10 years of unchecked selfishness.
Simply put, Brett Favre cared more about looking like the hero than he did about his team winning. His departure from Green Bay (and I include the episode last season where he called Detroit to give them Green Bay's plays out of spite) was probably the most illustrative behavior of the kind of player and person Brett Favre was...petulant, selfish, and above all loyal to his ego first and foremost. And his final few games and offseason with the New York Jets illustrated the kind of QB he'd become...one who had no interest in tailoring his game (and sharing credit) to get his team into the playoffs and who had no interest in supporting a team that wouldn't give in to his every whim (like trading him to Minnesota, even though it would cost the Jets a first round draft pick).
Like I said, we'll see plenty of puff pieces over the next few weeks from sportswriters who idolized Favre (often a result of Favre's strategy of cozying up to them personally by giving them "access"). Hopefully, a few sportswriters will be smart enough to look at him objectively as the QB he actually became for the last decade of his career.
(Author's note: I changed the headline. Not because there's any info coming out that Favre's not retired but mainly because he's played this game before).
Update: According to numerous sources, unlike his "retirement" with the Packers (shortly after which he tried to blackmail his way to Minnesota) this time Favre's already submitted his official retirement paperwork to the league office...so that appears to be a career for the former golden boy of Green Bay.