As of May 2012:
Basic Grading: 0-10 Hours Experience
4 Flights in Grob covering basic maneuvers & Aptitude
Intermediate: 10-30 Hours Experience
4 Flights in Grob covering basic maneuvers and PSL. Aptitude
Advanced: 30+ Hours Experience
3 Flights in Grob covering basic maneuvers, PFL, Circuits (normal & glide), and advanced aptitude. THEN...3 Sim sessions covering what holdmetight mentioned earlier.