It was a VERY good trade for all three times. I think this is the first time I have ever thought that about a three-way trade in the NBA.
Magic: They realized quickly that there was no way they were going to be able to compete with the Bulls, Knicks, Celtics and Heat and they took action early in the season. They were relying too much on Dwight Howard who is as overrated as they come. I don't mean to say that he's not a good player or even a great one. He is far above average at his position but he lacks the mental ability to play defense away from the ball and the Magic needed to add some size. Turkgolu did exactly that and of course JRich will help them on the perimeter.
Suns: Nash needed another offensive player to deal with. Marion is gone. Amare is gone. He needs offensive talent who are multidimentional and that's exactly what they got. Carter can drive the ball, drunk and shoot the three ball. Nash will work very well with him and his experience and leadership should boost the team. Carter can also play defense and doesn't commit silly penalties away from the ball.
Wizards: They needed to get rid of Arenas. His stats may look like he's had a very solid player but he's not even shooting 40% from the field which is unacceptable for a point guard. He's made a career out of taking too many shots and taking bad shots and when he's on, he's on. However, he is not on enough to be considered worthwhile as they transition to the John Wall era. The draft picks will help them build around Wall and things appear to be on the rise.
Very high remarks for the coaches, GM's, etc. who put this deal together.