From Steve Wyche at NFL.COM:

Vikings quarterback Brett Favre ran into a half-full Lambeau Field at 2:37 local time for warmups and was met predominantly with boos by the Packers faithful, who once cheered him for the better part of his 16 seasons here.

There were a smattering of cheers, but he was hit mainly with a negative vibe right out of the tunnel. The chiding didn’t last for long, though. Once he settled in around the 35-yard line near the Vikings’ sideline and began throwing passes with Sage Rosenfels and Tarvaris Jackson, most of the reaction turned toward the home team.

Not a great way to welcome back a team hero. Very small.