He's talking about forums though guys, or at least I think....I 'unno any more. Anyways, like people said, ther's a "tags" section, of which is under the popular games. Those are for subsections, and the bigger the font the more there is, or at least so I imagine.
I am sure that if there were a ton of them, and that there was enough interest, that we could add an extra section. But TD fits pretty well under the other genres. I think it would be too specific of a genre to put it up. There wouldn't be a whole lot that you could put in it, even though it is a pretty popular type of game.