To be clear, I'm not excited about the trade and think we should be getting more in return for Haywood, but let's keep the big picture in mind when evaluating this trade. 

1) This season is OVER. 

2) Haywood is unlikely to re-sign in Washington, so use him or lose him, contractually speaking

3) Caron Butler has been a major part of the problem (anyone who's played basketball knows ball hog = chemistry killer) and EG is looking for addition by subtraction. (As an aside, I won't be surprised to see a 2nd half push, a small one anyway, with Butler gone)

4) Stevenson's contract is awful

So...

EG is trading Butler to being repairing chemistry and giving the Mavs Haywood so that they will take on Stevenson's contract in the process. Who the Mavs are giving us in return is IRRELEVANT. They all have expiring contracts and will not be with the Wizards the next time a Wizards game matters. 

After this trade, the only players the Wizards are contractually obligated to for next season are:

Arenas ($17M)

Jamison ($13M)

Blatche ($3.2M)

Nick Young ($2.6M)

Javale McGee ($1.6M)

That's a total of $37M which will be about $15M under the salary cap (and possibly $28M under if Jamison is moved). Needless to say, the Wizards are going to be MAJOR buyers in free agency during the greatest buyers market ever. The cap went down thanks to the economy and only a handful of teams have major cap space and there are loads of good players available. 

Bottom line: This trade is meant to repair chemistry and get at least $15M under the salary cap for next year. Who cares at this point what happens the rest of this season? Losing Haywood will give development minutes to Blatche and McGee, which can still be seen as a positive. 

And on that note, happy trails Brendan Todd Haywood. A long-time Wizards, an underrated player and I'm sorry to see him go. (OTOH, Don't let the door hit you in your keyster, Caron "I'm an all-star" Butler)