Cribbs is a dynamic player, but like others have mentioned, will he fit in this system? What will he bring to the table with the Patriots?
If it's just his return abilities, then 2.5 mil over 3 years and giving up a 2nd or 3rd rounder is too much. If he is able to run routes, stretch the field, can also be a wrinkle in the run game, and return kicks, then yes, do it. What helps him is that he is a former QB and unlike Hester, develops his offensive skills quicker then most. Not a knock against Hester who made the transition from return specialist to WR and a pretty darn good one.
But if the Browns put him up for trade, they are idiots. And there will be a couple of teams with younger or newer offenses where Cribbs might go and develop with that offense. Chiefs, Dolphins, Redskins, Texans, Packers, and Bears.
Oh, and greatest (and saddest) comment for a Browns fan:
Great he will going to another team and win the super bowl on a returned kick or punt. I have seen this before. Earnest Byner goes to the skins after the fumble, wins the Super Bowl. History of my favorite team.