Must've been a bit cranky when I posted, but it is true that the champagne in DC is disappointing.
On the otherhand there are some outstanding sommeliers and service in DC. My wife and I always visit the 1789 on the occasion of our engagement anniversary and reserve the table where I proposed.
On our visit last year we decided to delve into good white wines, since we usually focus on the reds and felt like expermenting a bit.
The sommelier recommended a nice white (unfortunately I don't recall which one.) We both thought it was rather pedestrian and didn't drink much of it, commenting that if this is what good whites were about we would stick with red.
Imagine my suprise when I turned on my mobile phone the next morning and had a message from the restaurant. It turns out that they were suprised that we had left so much of such a good wine and decided to finish it off themselves.
After tasting the wine they decided it was bad and refunded the price to my credit card! How is that for uncommon service?
DC has some great restaurants with good cellars, just stay away from the bubbly!