LAS VEGAS — There is one class of people ill-represented at CES. Yes, the rampant, destructive force that is the teenager.

Here we are, witnessing the future, and the only teens here seem to be dressed in Lycra or shorts and trying to sell you a fascinatingly pointless accessory for your bicycle.

How convenient, then, that before CES opens its doors for a second day of joy, word reaches me of a teenage rebellion in social networking.

Yes, Facebook is passe. Dreary, dull, old. It’s the Wrangler jeans of social networking.

This sprightly information is courtesy of a survey performed by investor Garry Tan, a survey that BuzzFeed placed under my nose before breakfast.

It seems that for teens it is Tumblr that is de rigueur for the latest information about their innermost feelings. In this survey, more teens dedicated themselves (and their selves) to Tumblr than to Facebook, even though Tumblr is fairly tiny in comparison.

There are other deep teenage loves that emerge from this data.

Teens are very partial to Instagram. They outnumber adults there almost two to one. Naturally, Snapchat has also captured their imagination like, like, you know, like, sort of, it’s so cool.

These results concur neatly with an interview performed by Branch co-founder Josh Miller on his 15-year-old sister.

His (and her) conclusion was that Facebook “may have an irreversibly bad brand.”

Some might say that one indication of an irreversibly bad brand is when it tries to make as much money out of its customers any way it can, even if begins to annoy those customers.

That, of course, would never describe a free and bounteous service like Facebook.