According to their latest projections, which includes tweaks for minutes projections.  And that's while being generous and assuming Kobe Bryant comes back early.

The Celtics are being projected at 38.7 wins, which would be 9th in the east, within a range between 26.7 and 44.2 for good and bad predictions.  That's one of the wider ranges in the projections and seems to be because youth is just not reliable and could go either way.

They currently have
West: Thunder, Rockets, Clippers, Spurs, Grizzlies, Jazz, Raptors, Nuggets
East: Heat, Bulls, Hawks, Bucks, Cavs, Pistons, Wizards, Nets

To give you an idea of how their numbers work, if you ranked teams by their optimistic projects, the East would look like: Heat, Bulls, Bucks, Hawks, Nets, Cavs, Wizards, Celtics

The Lakers are the worst in their projections, with the next tier of awfulness being the Kings, Suns, and Magic.

The site does admit that the modeling needs to be adjusted further to account for minutes.  One example given is that they expect the Pacers to projected as a playoff team after later adjustment.