If he progresses at an even pace, I'd think Yorman would be in the OF by 2013 (possible a debut in late 2012). I'd hope that Puckett would be in the mix at 2B too - hopefully with solid power numbers.
I agree with Doug that this is highly unlikely. Yorman is very young and still raw. He has 4 levels left to go, so saying he could make it to the majors by 2013 assumes he can succeed at 2 levels in both 2011 and 2012. That's optimism bordering on delusional, given that this is an 18-year old Venezuelan who's going to have language/culture adjustments to make at each of his minor league stops.