Hanson, 26, was one of the Braves' heralded young pitchers a few years ago, but he has regressed since entering the majors. His ERA from 2009 to 2012 has gone from 2.89 to 3.33 to 3.60 to 4.48, due largely to an escalating home run rate. He also missed time in 2011 due to injury.
Hanson is arbitration-eligible this offseason, and is under team control through the 2015 season.
Walden, 25, is a Fort Worth native who was the Angels' closer in 2011, but who ended up losing his closing job in 2012. He's under team control through 20176. (Sorry, did the math wrong the first time)
This is an interesting deal, a swap of a disappointing young starting pitcher for a closer who lost his mojo last year. If Hanson gets his groove back, this could be a great deal for the Angels. If Hanson is for the Angels what he's been the last couple of seasons for Atlanta, then the Angels basically got a back-end starter.