Keith Law ranks the Pirates' farm system the third-best in baseball (Insider-only). Law notes that "almost everything went right" the Pirates' minor-league system in 2013, and that grabbing Austin Meadows made up for losing out on Mark Appel last year.
The Cubs rank fourth -- they're going to be really annoying here in three or four years. The Cardinals are 12th and the Reds 16th. The Brewers are dead last, and Law writes that "[t]here may not be a player in this system who projects as an above-average player in the majors."