Loved what IT did here, and his performance in Game 2 against the Wizards was one of the best individual playoff performances I've ever seen by a Celtic. But like others have said, not even close to having the body of work to merit a retired jersey. I'd retire Rondo's number way before IT's.
Also, while I understand that IT is likely pretty bummed about this, he still gets to play in the NBA and will likely be making max money a year from now. He'll be fine.