"First off, I'm a current Diamond member thru 2/2011 (which I earned thru the conventional way in 2010). I called the Diamond customer service line and was able to sign up for the fast track promotion using the code TRIALPL09. The CSR informed me that I will keep my Diamond status thru 2/2012 as long as I stay 15 nights within the next 180 days. So I'll hit my status again in 15 nights vs the traditional 50 nights.
So I hope that clears up any confusion for you current Diamond members. "