After re-reading this thread, I have decided to admit I was completely wrong. As a big Castro fan, I want him to be up as soon as possible. However, I don't want the Cubs to rush him. The last guy that I can recall that started at 20 years old was Cameron Maybin (who, I hate to say it, had more upside than Castro at this point). He was extremely rushed. When he went back to AAA, he dominated, and now he is back on track. In hindsight, they probably would have waited another year with Maybin and that is what I think we should do with Castro. On top of that, we have looked mediocre at best at SS for as long as I can remember. But one more year of frustration is completely worth a properly developed Castro in 2011.