If you're willing to trek up to Dupont Circle (Metro Red Line), Komi has awesome New American food. For oysters, check out Hank's Oyster Bar. Both are on 17th St.

In Chinatown (the "new" Downtown), I can highly recommend Zengo for Latin-Asian fusion, and IndeBleu for French-Indian fusion.

For upper brackets, I've always had great food at Citronelle in Georgetown, and arguably the best (and most expensive) restaurant in DC right now is CityZen at the MO|DC. Justifiably so, I might add.

For the suburbs, I'm glad someone mentioned Maestro (Tysons Corner) and Eve (Alexandria) coz they are both fiercely good!

Personally (and IMHO), I'd file Galileo, TenPenh, and Vidalia under "I'm not rushing back there anytime soon"