His BB% in 2008 AAA is irrelevant because he only had 69 PA. That is a very small sample size. BB% doesn't stabilize until 200 PA. http://saberlibrary.com/more/sample-size/ That means he would have needed about 3X the PA before we had any idea about his BB%
.313 OBP and .719 OPS in the big leagues and .309 OBP and .740 OPS in the minors.
I'd give more weight to his most recent period of play, since he's a young guy still developing.
In 2009 for 106 PA's, .301 .371 .505. That's not a weak bat at any position, much less catcher.