When it comes to cutting the cord – to traditional phones and cable services – there's no advocate group stronger than the millennials, according to the market researchers at GfK MRI.

The young adult millennial (ages 18-34) crew  accounts for "nearly half" (43 percent) of the U.S. cordless population – defined by GfK  as those who have never had cable, satellite, or fiber-optic cable service and those who have cut the cord.  And 30 percent of U.S. millennials are now cordless, compared with just 16 percent of Boomers.

These cord cutters' viewing habits — and even just their perception of TV —  differ from those of traditional television watchers, Gfk found.  "TV" gets defined as anything they can watch on any device – a TV, laptop, smartphone, or tablet.  Gfk reports that named favorites include usual streaming suspects YouTube, Netflix, Hulu, and Amazon Prime. But the younger viewers  also "over-index" (a GfK survey term meaning disproportionate usage) for smaller entities like Crunchy Roll, Twitch, and the Adult Swim App. And when  sitting down to watch TV or video, the study showed, the cord-cutters are most likely to go to a specific show on a streaming service, rather than  just surf.

Tapping this coterie is tough for marketers and opinion takers.  Millennials are hard to reach because they are "44 times more likely to be cord-free than the average US consumer," the study noted.

"While huge fans of quality programming and content ... they are not fond of being told where, when, and how they should watch it," said Karen Ramspacher, senior vice president of Consumer Insights and Trends at GfK MRI. "They view streaming services as well worth the money and producers of the best shows 'on TV.'"