I really don't have much of a reaction. I don't think this was some lame attempt to boost sales. She really doesn't need anymore money, and if she really wanted to appease the fandom she'd go ahead and declare Sirius as the gay one, and announce that there are clues to his and Lupin's secret love affair if you circle every fifth world in Chapter 21 while holding it up to a mirror upside down.
In retrospect though, I suppose I can imagine it. There are a few suspect lines in DH, but I didn't give them a second thought until now.