I'm pretty sure you dont get compensation picks for players that have been released, only unrestricted FAs that have been signed elsewhere.
One other person summed this up. Pittsburgh probably figured the compensation pick in 2008 would probably be a 3 or a 4... Jets probably didn't want to go that high.
Yeah, I'm not sure Pitt would get any compensation for releasing Porter. This is all I could find in regards to how you get compensatory picks http://www.nfl.com/draft/story/9341500
But as someone before me said, you don't get compensated for guys you cut, only FA's. And btw, to the person that can't see why trading for him would be better then signing him: We'd be the only team able to sign him, and instead we're now in a 5-10 team battle for him.
Good point, I forgot about that. I frankly think that the Jets decided they didn't want the player at 5M. If he goes for more, they probably won't be interested. They also could have wanted to renegotiate and Porter wasn't interested... who knows what is going on there. You are also goin on the rumor that the Jets tried to deal for him is FACT when it may be all made up or just not true.