Flingo is best known as “the video start-up run by the guy who used to run BitTorrent.” And so far, CEO Ashwin Navin has been concentrating on building “smart TV” apps that you’ll find on sets from Samsung, LG, etc.

Now the plan is to put the new money into software that will automatically figure out what viewers are watching. That way, it can bring them more information about what’s on the screen, and/or help them tell their pals about it.

And that, theoretically, could help Navin grab a piece of the very big TV advertising pie.

But that plan puts Navin in the same place as several other “TV check-in” services, like GetGlue and Yahoo’s IntoNow. And all of them face the same really big challenge: How do you get people to use this stuff?

It’s not that people aren’t interested in telling their friends what they’re watching. It’s just that they’re already doing that, on Twitter and Facebook.

That doesn’t mean a specialized social service that works with the existing ones can’t take off — that’s one of the big takeaways from Foursquare and Instagram.

But it does mean these check-in apps have to provide something pretty great. Or the second-screen real estate is going to get claimed by folks like Mark Zuckerberg and Dick Costolo.

Bragiel bragged that of the six I/O Ventures companies from last year, one has been acquired (Facebook fan page creator Damntheradio by FanBridge), one is in late-stage acquisition talks (online video monetization platform SocialVision), three have raised funding of at least $400,000 from investors such as Max Levchin and Dave McClure, and the last (experience marketplace Skyara) is closing a funding round.

While I/O Ventures will continue to run with a curriculum quite similar to other start-up programs–soliciting young folks who have an idea but not much else, for a few months of intensive mentorship and events, followed by a “Demo Day” for investors–it has a few characteristics that set it apart. Mainly, the program is located in a building owned by its founders in the happening Mission District, home to a newly opened cafe called The Summit, which has become a bustling space for techie meetings and laptop sessions.

Bragiel said he expects to accept five to six companies once more, rather than swelling to a larger class, as Y Combinator has done. The program pays $25,000 and waives rent in exchange for eight percent of a start-up’s common stock. This year’s edition will include more events and more hand-holding around the initial company formation process, Bragiel said.

I/O Ventures continues to be funded by its four founding partners: Bragiel (who recently sold his forum company, Lefora), as well as BitTorrent co-founder Ashwin Navin, HotorNot co-founder Jim Young and Myspace co-founder Aber Whitcomb. It will accept applications through Feb. 15, with the sessions starting March 1.

This is old news, literally: Chen left his spot as chief technology officer last fall, though he remains employed at Google (GOOG), which bought his company for $1.65 billion in 2006. “Steve shifted his focus to help with some Google engineering projects. He’s still involved with YouTube and invested in its success,” says YouTube spokesman Ricardo Reyes via email.

Google hasn’t officially named a replacement chief technology officer for Chen, and people at the company say the job no longer exists. But the highest ranking engineer at the company is now Louis Perrochon, who has been at Google since 2003.

Chad Hurley, who co-founded YouTube with Chen and Jawed Karim in 2004, remains the company’s CEO. But it’s not unusual for founders to move on from their companies within a few years of selling them.

The fact that Chen’s move  has gone unreported until now should underscore that his departure didn’t represent a major org chart reshuffling. The technical challenges of the site have long been handled by a large engineering team, which makes sense considering that the challenges themselves are large. YouTube now uploads 20 hours of video per minute.

Chen was reportedly working on a technology incubator project last fall along with BitTorrent co-founder Ashwin Navin; no word on what Chen is actually doing at Google now.

Here are Chen and Hurley in a video they shot and uploaded on Oct. 9, 2006, the day they sold their company to Google.