All the pundits keep assuming that the Celtics will end up with a lottery pick because they traded away Garnett and Pierce. I am not convinced that they'll be any worse than they were last year. In fact, it wouldn't surprise me if they finished with a better record.
The team's biggest problems last year were: 1. age (the three oldest on last year's roster are now gone), 2. rebounding (Humphries, Iverson, Olynyk, Melo should help there), 3. health (Rondo, Sullinger should be ready to start the season), and lack of scoring punch off the bench (Brooks and regular playing time for Crawford and Lee should boost the shooting depth).
Throw in the emergence of Jeff Green, the addition of a solid veteran like Gerald Wallace, retention of decent to good rotation players like Brandon Bass and Avery Bradley, plus whoever the Celtics might sign with the MLE, and this is a team that can definitely compete for a 6-8 seed in the Eastern Conference.
After Miami, Indiana, Chicago, and Brooklyn, probably New York and Cleveland too, I don't see any Eastern Conference teams that are clearly better than the Celtics as currently constituted. They're at the same level as the Sixers, Hawks, Raptors, Bucks, Wizards, Pistons, etc., and still better than the Bobcats and Magic.
To truly contend for the top pick in the draft, the Celtics need to make some additional moves. They can get away with keeping one of Green/Rondo, but not both of them. Teams with two legitimate All-Star candidates generally make the playoffs.
I would look to trade Rondo to somebody who will also take two out of Bass, Wallace, and Lee. If the Mavericks fail in their pursuit of Howard, Dallas could be one option, as reported. Another good option would be the Golden State Warriors.
To Golden State: Rondo (2 years remaining), Wallace (3 years remaining), Lee (3 years remaining).
To Boston: Biedrins (1 year remaining), Jefferson (1 year remaining), Rush (1 year remaining), future 1st round draft pick.
This trade would clear up a ton of cap space, net an additional draft pick, and ensure that the team is sufficiently bad this upcoming season.