New Harry Potter book a Marketing Trick?

I read yesterday, on New Years Eve, that JK Rowling hints that she might write another book about the young wizard Harry Potter. I am not sure what to think about this information. Well, at first I am kind of jumping up and down, looking forward to read yet another great book. But at the same time as I am jumping of joy, I find myself standing in midair, thinking about why JK Rowling is revealing this information. To me, this is almost as when she told that Dumbledore is gay. I have nothing against hints, and I would love to read another Harry Potter book, but why is she revealing this information now? Is it really just a marketing trick, so we won't forget Harry Potter? Or maybe Neil Strauss did the interview after he released his book The Game (LOL)? I am not sure if it might be a marketing trick or not, and I like to think that authors are not good marketers, but some of them really are. I like to believe that everything the authors tell us will be straight from their hearts and minds, it's all about the story and what they believe they have to write in order to complete the story. Is this the case of JK Rowling and Harry Potter? Well, I don't believe that Harry Potter will need more fans than he already got, and the timing is not that good to reveal another Harry Potter secret. The seventh book was just released a few months ago, it would have been a lot clever to release this information in six months or so (or maybe even later). Today, most people are still reading Harry Potter and most people won't forget him or JK Rowling for a long time. Well, I don't believe that we will ever forget any of them. So, this information from JK Rowling about the hints of a new Harry Potter book are to me just her telling us what's on her mind. Or maybe I am wrong, maybe this is great marketing from a great author?