Though not a true FF program it does seem to be one of the more lucrative around now - especially if you happen to make a lot of 3 or 4 night stays.

1st 3 night+ stay = $50 Amazon gift certificate
2nd-10th 3 night+ stay = $50 Amazon gift certificate or 1 free night.

As a rough comparison to the Marriott's Residence Inn.

$100 night * 3 nights = $300 = 1500 MR Rewards points
18000 points = $50 Marriott check
Though a closer match would probably be the GPB25 Virgin Megastore certificate for 22000 points
7500 points gets a one night Category 2 point saver.

So if you happen to be making a number of 3 night stays and have a use for Amazon gift certificates or quick free nights, the promotion is one of the most lucrative around.

However, if your looking for elite status or variety of awards, its pretty worthless.

I still have to wait and see how long it takes for the certificate to get here...