For years TV has used the glitz and glamour of its primetime dramas and comedies to spur spending from advertisers. In 2015, the big networks have instead called in the nerds.

At a colorful presentation by CBS held Wednesday, actress Mayim Bialik played her geeky character Dr. Amy Farrah Fowler from the network’s hit “The Big Bang Theory” to help communicate the network’s willingness to sell advertising based on consumer data from its clients. To bring the message home, CBS ad sales chief Jo Ann Ross took the stage dressed just like Bialik.

As Madison Avenue grows increasingly fascinated with the precision offered by digital media, the TV networks have to try to look the part. For the past few days, as big companies like Comcast, Walt Disney, 21st Century Fox, Time Warner and CBS made presentations for TV’s annual upfront market, when they try to sell the bulk of their advertising for the coming year, they portrayed TV – the biggest audience-assembler in the media landscape – as something that could also deliver niche audiences thanks to the use of new technology.

We’re big, the TV networks reiterated, but we can also be small if you need us to be.

Case in point: ABC’s ad-sales chief Geri Wang unveiled new initiatives to help advertisers reach particular groups of consumers, including a new tool that matches viewing-habit information culled from set-top boxes with consumer data provided by individual advertisers. “If you’re a retail client, you could weight your programming mix towards shows that over-deliver apparel shoppers,” Wang explained. “This takes television beyond the traditional demographics, allowing for more data and personalization.”

In similar entreaties, NBCUniversal ad-sales head Linda Yaccarino talked about advanced ideas made available from data provided by parent company Comcast, and Turner ad-sales chief Donna Speciale discussed the concept of buying audiences based on data findings rather than the time a program may be on TV.

Whatever happened to just running ads alongside TV shows?

That concept is becoming an outdated one, so the companies that sell such stuff have to tell a story about “premium video” that is “consumed on demand,” no matter what type of media device a viewer, streamer or surfer might use.

Consumers “don’t stop to think about whether they’re having a TV experience, a digital moment, a radio or print experience or, for that matter, a social engagement,” said Ed Erhardt, president of global sales and marketing at Walt Disney’s ESPN during that company’s presentation on Tuesday. “They don’t see the lines.”

It’s difficult to think of a “Big Bang Theory” or “Grey’s Anatomy” or “Gotham” as just another digital file that gets streamed on a palm-sized screen as someone rides the train to work or sits outside on a bench waiting for a friend to meet to go to dinner. As a new generation of viewers accustomed to content that is always available grows in economic stature, however, that is exactly what pieces of video entertainment known as “TV shows” are fast becoming. Selling them becomes less a game of showcasing celebrities, laugh tracks and cliffhangers and more one of making certain advertisers can send the right ads to the right consumer niches – soda drinkers, first-time car buyers, expectant families – at whatever moment these people might be online to receive the pitches.

To be certain, quality still matters. After a tiring spate of “NewFronts” held recently by TV rivals ranging from Conde Nast to Vice, ad buyers marching to this week’s presentations said they remained wary of programming from some of the digital companies. Advertisers get little feedback on performance, they said, and many of the shows being pitched to them come to fruition only if they can get an advertiser to back it. With the TV networks, these buyers said, the programming is nearly guaranteed to launch and is of a certain standard upon which they can rely.

With that in mind, some of the media companies tried to super-serve Madison Avenue. Fox’s presentation gave a good chunk of the spotlight to sister outlets like FX and National Geographic Channel. At ESPN, ABC’s Wang appeared while the two units offered packages of content like a wild card NFL broadcast simulcast on ESPN and ABC; a morning-show offering comprising both “Good Morning America” and ESPN’s “Mike & Mike” radio program; and a New Year’s compilation of college-football championships on ESPN as well as ABC’s “New Year’s Rockin’ Eve.” If advertisers want a certain grade of content, the theory seems to be, maybe they’ll buy more of it.

Keeping track of it all means counting up piles of audience from TV viewing, DVR playback, mobile streaming and more – even though the industry has yet to agree on how do so so. No wonder CBS trotted out a fictional neuroscientist to woo clients Wednesday evening. In 2015, entertainment matters, but analyzing the path that entertainment takes on its way to being seen by consumers matters a lot more.