I have been using RAD 7.5 Beta since last year and recently I am getting "Expiration Messaging". I just checked it and it will expire in two 2 days. Hence, I think the license expiration for everyone will expire in September 12. (Hopefully the full version is released soon). [ September 10, 2008: Message edited by: Jair Rillo Junior ]
There are a number of betas out there with different dates. I used one that expired 2 weeks after I got it (early in the summer) and another that expires this week. I don't remember the date, but September 12th sounds familiar. The idea being that people wouldn't be reporting bugs against a really old beta. Hopefully they come out with a new beta with a later expiration date until the real version comes out.