Seems like a fit for the Hotel Deals forum.

Also, you have to book a paid night with them before you get your free night cert. Yes?

You will also receive a coupon code for a free night in your confirmation email. The coupon code will be activated immediately upon registration. Just make a qualifying booking on hotels.comŽ using the coupon code and complete the stay by November 15, 2011. After we have verified your activity in three (3) separate major hotel loyalty programs, and after you have completed your qualifying stay by November 15, 2011, your account will be updated to reflect the free night. Remember that you have forty-five (45) days to send in your statements after your registration in order to qualify for the free night.