The original Highway and City tests are still in use for CAFE. No change there.
In 1985, the numbers were adjusted down about 15%, to make the ratings more "realistic". Still the same test, just reported with an adjustment factor.
In 2008, 3 more tests are added. High-speed (70mph, harder accel), Hot (hi-temp, AC), and Cold (same city test, just colder temps). These are averaged with the old tests (adjusted) and reported on the sticker. Approximately 15% extra reduction.
So, the CAFE 35mpg means a 85-2007 epa rating of about 29.8, or a 2008+ rating of 25.3.
http://www.fueleconomy.gov/feg/fe_test_schedules.shtml