Well, nobody saw this coming. Selected by Milwaukee, Wang is a left-handed pitcher signed out of Taiwan in October 2011. I have absolutely no idea how he could have been eligible for the Rule 5 Draft, except that some of his time pitching in Taiwan must have counted. He missed all of 2012 while he was recovering from Tommy John surgery, then had a good debut in the GCL this year. His out pitch is a curve and he has a fastball that was reaching 90-94 this season. Given his experience level, I find it hard to believe that he'd stick with the Brewers.
The Pirates selected nobody. In fact, most teams selected nobody. Only nine players were taken in the major league phase, seven of them pitchers. Zach Thornton, whom Baseball America characterized as likely to be selected, was not selected.
UPDATE: According to Tim Williams, the explanation for Wang's eligibility is as follows:
The reason Wang was eligible here is because his original contract with the Pirates was voided. The Pirates originally signed him for $350,000, but the deal was voided due to medical concerns which led to Tommy John surgery. They re-signed him to a second deal and he underwent the surgery. Any player whose original deal is voided becomes Rule 5 eligible the next draft, no matter when they signed their contract.
The Brewers obviously don't have Larry Doughty running the show.