Yeah, James held up NBA business for 11 days while he decided his future. Teams were angry. Some had assets that evaporated during the wait, including the Warriors, who considered Brandon Bass and other names in exchange for a trade exception that expired yesterday at midnight.
There's no mention of other assets exchanging hands so it is possible that draft considerations would have been exchanged as well. However, it might have been worth it to Boston just to move Bass to get out of the last year of his contract.
Consider the financials behind making a move with the Keith Bogans unguaranteed (immediately waivable) contract. If you coupled that with the rest of the other non-guaranteed guys (Babb, Johnson, Pressey) you could in theory bring back a player making $7M. The problem with all of that is that the Celtics are already over the cap and right up against the tax line. Unless they are bringing in Kevin Love, I don't think the management would be willing to pay it. Nor should they, considering all the negative penalties the tax brings with it (restrictions on free agent signings, etc.).
Of course all of this is fluid. Trading Bass might have been a contingency plan of a contingency plan that we know nothing about. I'm sure Ainge has a lot of balls in the air right now.
Also, there's a good chance that Brandon Bass (and Jeff Green for that matter) could still be traded this offseason. The Kings just created a $7M trade exception with their Thomas sign-and-trade. Other teams have cap room and can use it to absorb contracts. I wouldn't put it past the Cavs to look for some solid veteran big man help to put around LeBron James.
The bottom line is that things are just getting started. Bass may or may not be on borrowed time here.