I have not been to Búzios in a long time, but I am going to make an effort to spend a weekend there this summer (and by summer I mean winter in the Northern hemisphere). The city has been investing a lot of time and money lately in gay tourism, which I fully support.
If you don't want to be stranded on the beach tanning and watching the birds, you will be glad to know that circuit parties are not out of the question in Búzios. This past weekend the city celebrated its first annual Pride Fest with seminars and a big bash at Club Privilège. Check out pictures of the festivities at G Online.