I think Tapia's two-seamer/changeup combo will get him to the big leagues. They are that good. Mike bemoans the fact that Tapia does not throw a slider in games. The general scouting consensus is that without that breaking ball, he will land in a bullpen.
Good stuff from old friend Mike Newman on Domingo Tapia over at Fangraphs. Mike spends some time musing about the relationship between Tapia's four-seamer, his sinker and changeup.