Pretty bored, so the reason I'm excited about Smart, in short-form:
1) Body: Has athleticism and strength to get the step and finish in today's NBA. By today's NBA I mean the one where nobody touches you until you get 6 feet within the basket. I see this guy shooting over 8 but closer to 9 free throws per game before the end of next season. It's a combination that doesn't need much nurturing or maturation from a guy who is already probably about 80% there. Its also a skill that won't go away til he's like 29 or 30 if his body holds up.
2) Mental makeup: Hot head, maybe. But the passion is more what interests me (TWSheedS). He cares about competing, he cares about winning, and wants to be 'The man'. Like you (LB33) I don't really see a high percentage play for the Celtics in keeping Rondo long-term. I'm sure it exists, but I just don't have a vision of it being likely (IE, I'm not sure who 'The Guy' is that we'd get that we haven't already pursued already). Marcus Smart looks like the type of guy who will do well being thrown into the fire of a losing season. Somebody who will come out stronger knowing what he's missing rather than someone who becomes accustomed or indifferent to it.
3) Skills: This is a bit of a tag-along to number 1, but he's got the ball-handling and body control to get to the hoop and finish, he's got good (if not elite) passing skills, and he's a tenacious defender. That's now. I won't pretend he's ever going to be a better than average (or hell, even average) 3pt shooter, but you don't need him to be if you construct your roster properly. His skillset is already basically there, needing refinement more than development.