Box Score Geeks is the heir to NBA Geek, a stat site associated with Wages of Win relying heavily on Wins Produced.  They've rolled out their NBA previews.  Their predictions aren't far from what WoW was saying earlier in the off-season with tentative numbers; they still have the Lakers as the worst team in the NBA, for example.

They give the Celtics a 53.4% chance of making the playoffs, a 19.8% chance of winning the division, and a 94.5% chance of surpassing 27.5 wins.

Here's what they say:

I think the right play is to wait and let this young team have some fun. If the season goes well, Rondo comes back and the right desperate trade partner comes along (say Denver with Faried, LA with Pau or the Timberwolves with Kevin Love), you pounce and compete now. If it doesn't, you shut it down after the break and improve your draft position. I'd keep Rondo (a la Pierce), focus on building up my flashy big (Kelly Olynyk in the Big Al role?) and possibly look to put together a package of attractive assets for a pre draft trade.

I think it comes down to a series of unpredictable events. I trust Ainge to make the right choices though.

I generally agree with the take of Patrick Minton:

This team is a real enigma. It has all the potential to be an "over-achiever" that wins Brad Stevens the coach of the year award as a rookie coach, but unfortunately, there is a ton of room for Boston to implode, either on purpose or accidentally.