FanGraphs takes an in-depth statistical look at whether or not Martin Prado's stellar season is a fluke. Money quote:
The key is Prado’s ability, at least so far, to reach base on balls in play. In 1139 ABs so far, Prado has racked up a .344 BABIP. Given how long it takes for BABIP to stabilize, we have to assume that it will drop in the future. However, the longer Prado can keep it up, the more we have to figure that this is real, and his excellent 20.9% LD rate is certainly evidence in his favor.
So, to answer the question, Prado is quite good. The fact that his playing time is way up and the fact that he’s played at an all-star level, however, lead us to another question. Is he getting better this year, at least at the plate?
Definitely worth a read, though I'm not sure the question is really ever answered. There's still a what-and-see approach with Prado, as he must avoid a large second half regression to silence the critics.