Castro has an enormous hype machine behind him at the moment. He was well-regarded at the end of the minor league season since he put up good numbers at the plate in High A and AA and because he had garnered a strong defensive reputation. However, he went to the Arizona Fall League and everyone went completely nuts over him since he's posting a very high batting average and has made some nice defensive plays. He's doing an excellent job for a 19 year old. There are still some concerns about his power, ability to maintain his batting average at higher levels, and some lingering questions about his high error totals in the minors. During the offseason, you will likely see a lot of people name him the Cubs' #1 overall prospect. Baseball America might name him a Top 30 prospect in baseball. Whether or not the hype behind him is merited is another matter altogether, but he's got people talking. Also, the farm system has substantially improved from last year. Overall, the Cubs' system should rate somewhere around the middle of the pack compared with other teams.