We've reached both extremes "couldn't be happier", and "utterly disgusted" already, in the first 3 posts in this thread. I could (couldn't?) care less about whether the character is gay.
If his sexuality is a factor in the story line, ok fine, move along. If it's not a factor, then why is there this big annoucement by Rowling? Seems like it's much ado about nothing - probably to keep the Potter franchise in the public eye more than anything else, during a lull between books and movies.