The miles & bonus miles from my Hertz rentals seem to post fine for me. There may be some missing, but I haven't really checked.

Two examples:
Dec. 25-Dec.27 rental
Posted on Jan. 4
Activity date Dec. 25

Dec. 27-Jan. 3 rental
Posted on Jan. 11
Activity date Dec. 27
The "HERTZ CAR RENTAL (5+ DAYS)" and "HERTZ DOUBLE MILES PROMO", each 500 miles, both counted towards 2006 cal. year Preferred status.

This was same car as the previous rental, but not from an airport. I don't feel like paying for Houston's stadiums, etc.