As I did last year, I offer this teaser to Thursday's ranking of the Top 100 prospects in baseball by ranking the 30 farm systems based on the current inventory in each organization. This ranking includes only players who are still eligible for the Top 100 prospects ranking -- that is, players who still retain rookie status for 2010.
A system that recently "graduated" a number of top prospects -- Oakland, for example, with Brett Anderson, Trevor Cahill, Vin Mazzaro and Andrew Bailey losing eligibility for the ranking -- will rank lower on this list because I'm considering only what is currently on the farm. It's a snapshot look rather than a look back over a year or two of farm productivity. So at the bottom you will see a mix of teams that have graduated or traded good prospects in the last year and teams that just haven't done a very good job of stocking the system.
Within each system, I considered the entire list of prospects but gave much more weight to top prospects, particularly high-impact prospects, than to organizational depth in average to fringe-average prospects. I also considered how much major league value each organization is likely to produce over the next few years. So a system with high-impact prospects who are relatively close to the majors ranks high, even if the system lacks depth in second- and third-tier prospects. Of course, a couple of impact prospects plus organizational depth is ideal.