I'd take him in a heartbeat. This guy is not Chad Brown, he's a tackling machine, much more in the mode of Bruschi. He's not too old. I think two years ago he led the NFL in tackles (or was top three anyways) playing a 3-4 inside backer, and he's younger than Phifer was. If we could do a re-negotiation, it would be a GREAT signing. It could happen, we have the extra draft picks to trade, and Edwards has said he desparately wants a ring, so he may be willing to sign a new deal. I'd feel so much better with a Vrabel-Bruschi-Edwards-Colvin starting lineup than any other permutation discussed previously this off-season.
I'm going to go out on a limb and put this at a 20% chance of happening.
Edit....Edwards turned 33 last week. I'd be more than happy to give him a three year deal. We might all have to stop this "Patriot ILBs must be over 250" line though, he's listed at 227 at NFL.com. Here's his recent numbers, games played and tackles:
2001 Kansas City Chiefs 16 129
2002 San Diego Chargers 16 128
2003 San Diego Chargers 16 161
2004 San Diego Chargers 16 150
2005 San Diego Chargers 16 152
And, I seem to remember him filling in at Strong Safety before. I can't think of one good reason NOT to trade for him.