Desktops aren't going anywhere until laptops catch up to desktop performance on video games and graphics in general. The only reason I have a desktop is for gaming. I imagine most people who buy new desktops now only get them for gaming. I mean honestly, who would choose a desktop over a laptop for anything unless they need to interact with graphics heavily. I suppose you can get a more powerful desktop for cheaper than an equivalent laptop but I think this is a minority case.

(Just my thoughts, no data whatsoever to back this up).