I'm so excited to see what all the talk is about. The show is running at The Kennedy Center from now until April 3, 2010 and I believe tickets are still available. Visit the Washington National Opera's page on Porgy and Bess for more information about show times and to purchase tickets.
More information about Porgy and Bess taken from Wikipedia
Porgy and Bess is an opera, first performed in 1935, with music by George Gershwin, libretto by DuBose Heyward, and lyrics by Ira Gershwin and DuBose Heyward. It was based on DuBose Heyward's novel Porgy and the play of the same name which he co-wrote with his wife Dorothy Heyward. All three works deal with African American life in the fictitious Catfish Row (based on the real-life Cabbage Row) in Charleston, South Carolina, in the early 1920s.
Originally conceived by Gershwin as an "American folk opera", Porgy and Bess premiered in New York in the fall of 1935 and featured an entire cast of classically trained African-American singers—a daring and visionary artistic choice at the time. Gershwin chose African American Eva Jessye as the choral director for the opera. Incorporating a wealth of blues and jazz idioms into the classical art form of opera, Gershwin considered it his finest work.