My first two links as an editor involve the Rangers. I feel lame. However, this post is just too un-lame not to get linked.
Trip Somers (BtB poster NoNameOnCard) does a fantastic analysis of how Nelson Cruz has managed to seemingly turn his AAAA player label on its head by looking at his plate discipline via PITCHf/x and FanGraphs data. What I find to be fascinating from a general baseball stand point, even if you don't care about the Rangers, is his methodology. I think this kind of approach to studying how hitters are doing what they're doing would be great to see more often.
Trip, by the way, knows more about many things than I think I could ever hope to and even for non-Texas fans, it's the kind of blog you could do well to add to your list.