As heard in the Dice Tower, Episode # 116 - February 11, 2008

These are games that we think are the "next step", after the Gateway games.  These are games to help someone ease farther into the hobby, so they can play the heavier games - like Age of Steam and Die Macher.

Mary Prasad also gave a list.
1.  Pillars of the Earth
2.  Notre Dame
3.  Tichu
4.  St. Petersburg
5.  Caylus Magna Carta
6.  Amun Re
7.  Empire Builder
8.  Um Reifenbreite
9.  San Juan
10.  Bausack