Having just come back from a long weekend in DC, my vote would be for Florida. I see AirTran flies into Orlando and Ft Lauderdale. My favorite in Orlando is the Marriott World Center, but it's a Category 6 and will run you 55,000 points for 2 nights, as is my 2nd favorite in Ft Lauderdale, the Harbor Beach Marriott. However the Renaissance Boca Raton is only a Category 5, and while not on the beach, has a very nice pool area with a tropical feel and a large pool bar right next to the pool, and 46,000 points for 2 nights. Also lots of shopping and restaurants close by (walking distance even)

Keep in mind that in the summer you can get the South Florida properties pretty cheap even if you're not using points. The Boca Renaissance I have gotten for $130 or less including breakfast. Pair that with an EEO or a BB, or both if its 3 nights and you could end up paying under $200 for 3 nights.

Cindi