Apparently, Mike A. reported it yesterday but I only noticed it this morning. The Yankees' own Austin Jackson made MiLB's Top 50 prospects list, coming in at number 49.

Jackson is a tremendously athletic outfielder who, upon being promoted from the South Atlantic League to the Florida State League, responded to the challenge by showing the ability to hit to all fields with power, speed and more defensive ability than he'd shown in the past.
...
He'll play the 2008 season at age 21 and could feasibly do it with Double-A Trenton.

Getting onto Top 50 lists could definitely help that trade value...not that A-Jax hasn't boosted it considerably himself in the past year, becoming (arguably) the Yankees top position prospect.