Letting Favre play somewhere else would be a major mistake for the Packers. When Rogers goes down or plays poorly (or maybe both) they will need old wishy washy Bret. If he's playing well for another team and the Pack tanks, the FO will look like a bunch of idiots.
Is this whole 3 year saga getting old? Yes
Does Favre seem to crave the attention? Of course
Can the man still play some football and make a team better than it actually is? Absolutely!