Really? I think the HN bubble would lead to thinking more people have desktops than laptops. Many casual computer users don't even have desks to put that desktop on, they just use a laptop on the couch, when they run into something they can't do on their phone or tablet.

Agreed. Since the days of the $400 laptop started, most non-techies I meet don't have working desktops anymore. Almost all techies I know have one or more.