Details are here: http://api.metadatalabs.com
You'll find a couple of working sample apps, VideoRoulette and VideoDeck, which will give you a feel for what's available in the firehose.
debsnews is a video news service built on top of the firehose:
http://debsnews.com
The UI model has elements of both Twitter and Hacker News / Reddit. Channels follow a link structure much like Twitter. Every channel has two views: A real-time feed under "Most Recent" (like Twitter) and under "Most Popular" a rank based on popularity decaying over time (like Hacker News, Reddit and others.) You can rapidly skim the most popular news videos or spend more time and dig down into details.
We're so close to the problem and we've been at it so long that it's become hard to tell if what we have is actually useful or if we're deluded. We're eager to hear what you think. Feel free to respond here on HN or contact me directly: david at metadatalabs dot com.
Thanks!