I just got some more details - a list of the qualifying lenses and the rebate amounts:
200 f/2: $500
85 f/1.2: $130
50 f/1.2: $100
16-35: $100
45 f/2.8: $80
24-70: $80
100 f/2.8 IS: $65
15 f/2.8: $45
135 f/2.8: $35
100 f/2: $30
580ex II: $25
430ex II: $15