The clincher for me is that the guys who had him and saw him all of last season, the Jets, let him walk.
That, IMHO, is a loud, clear, unarguable message. No team lets a valued piece of their offense walk. Especially one who is, by some accounts I've seen in this thread, was "productive" in the scoring zone and is willing to sign - again, if you believe the rumors - is willing to sign for league minimum.
And when you look at the Jets' depth chart at WR you see Santonio Holmes and a bunch of whodats. So if Burress is still "all that" why didn't the Jets re-sign him? ...especially at league min??