I think he is. First guy off the bench type thing, 3-4 guy. Probably start on quite a few teams, no?
The Slater kid on the other hand...
The Patriots would save $130K by cutting Slater, vs. $2.5M by cutting Green. The two players aren't really comparable in any way.
The one thing that Green does have going for him is that this is the last year of his contract, and that cutting him would be a $2.5M cap hit. So, unless Belichick thinks he can get comparable production for less than $2.5M, there's no point in cutting Green.
Right now, the Pats have two high-priced defensive linemen in the last year of their contracts, Seymour and Green. Cutting Seymour would save $3.3M in cap space (with a $6M hit), and cutting Green would save $2.5M (with a $2.5M hit). So, anyone who thinks that Seymour is getting the axe (and there are a lot of people on this board who think that), is essentially saying that Seymour isn't worth $800K more than Green.
I'm certainly not banking on either one of them being cut, but if anyone on the defensive line is going, it'll probably be Green. It wouldn't surprise me at all if that happened.
There's also a chance that the Pats could extend him now, lowering his cap hit this year, on the premise that they won't be resigning Seymour so he'll become a starter in 2010. I think that Green is a substantial downgrade from Seymour, but if that's what it takes to lock up starting talent, then so be it.