RC has a special promotion when you pay with any AMEX card under their Summer Package.

Stay for 3 nights, pay for 2
Stay for 5 nights, pay for 3
Stay for 7 nights, pay for 4

Daily American Breakfast for Two
Daily Internet
Overnight Valet Parking
Ritz Kids

Plus, receive a room upgrade when you book the Summer Package and pay with any AMEX card from May 1 - Sept 30, 2009.

Here's a website with the promotion. Not sure if it's all days at all properties ... or what.