Mavericks: This was a good deal for the the Mavs. They got their man in Shawn Marion, who will give them another athletic scorer. Marion might not be as good of a player as he once was, but he still averaged 13 points and 8.5 rebounds a game last season. Humphries and Buckner should round out the Mavericks bench as well. This move might not equal them with the Spurs and Lakers, but it should keep the Mavs in the thick of the playoff race.
Raptors: The main reason they were a part of this deal was to get the sign and trade exception against the salary cap. Hedo Turkoglu was going to be a Raptor one way or another. This move just allows Toronto to have more cap room to potentially make further deals. Adding Turkoglu was a good move for the Raptors. He showed in the playoffs with Orlando that he's a big game player. He should mesh well with Chris Bosh on the front line and give Toronto a good presence on the wing. Both George and Wright can be solid depth players at the end of the Raptors bench.
Grizzlies: Memphis will release Jerry Stackhouse since his contract isn't fully guaranteed. The Mavericks will send cash to cover the expense, and add a little money to their coffers. They also get a future 2nd round pick. Not a bad return for a guy they were gonna release anyways.
Magic: The Magic don't receive any players or picks in the deal, but do pick up a valuable trade exception worth approximately $8 million. This should allow them to add another player or two for another finals run. It is interesting that the only team that benefited from the Magic being part of this deal, were the Raptors. A team that very well could be facing the Magic in the postseason next spring.
Winner: This was one of the crazier trades in recent NBA history (and that is saying a lot). Every team won and lost in this deal. The biggest winner would be the Dallas Mavericks as they needed the trade to fit Marion under the cap, and didn't lose anything of value. The biggest loser in this deal might be the NBA labor agreement that forces such ridiculous trade scenario's. The fact that the Magic only "receive" a trade exception and not any tangible money, players or picks is a bit crazy. As is the fact that the Magic get anything from a player who in reality left in free agency. I think the NBA should close some of these loopholes, and eliminate these hurdles in their CBA (*Note I don't want to see the salary cap eliminated just these crazy exceptions and such). They should let these teams build their rosters based on talent and true value, instead of Monopoly money being given in return.