Veuve Clecquot yellow label certainly seems popular. It retails for $32 or so around metro DC. Certainly one of our favorites, but we also sometimes pick up Pommery for sentimental reasons (a bottle was gifted to us on our honeymoon by a lovely UA flight attendant). ^
Washington Post ran an interesting champagne buying guide in their food section this week (free registration required):
http://www.washingtonpost.com/wp-dyn...122700203.html
(edited to fix bad grammar!)