Social networks Facebook and Twitter have long influenced the news while discussing it. They were key forces in driving the revolutions that lit up across the Middle East and Africa earlier this year, for instance.

Over the weekend, social news site Reddit also threw its hat in the ring. As we reported on Saturday, Redditors covered Hurrican Irene, live.

The social news site set up r/Irene on as a kind of citizen-journalist hub, a place for people to share stories, pictures, and advice for those in the hurricane’s path.

On Saturday, the section’s readership leaped to about 1,000. By early this morning, it was nearly 2,000.

As on Twitter or Facebook, people mostly posted photographs from cell phones: a house shorn in half by a fallen tree in Virginia; a sandy New Jersey coastline gutted by storm surge; a stretch of Long Island sidewalk yanked upward by overturned trees, leaving behind a yawning gap.

And like every post on Reddit, users jumped into the comments to provide context.

That line of fallen trees in Long Island, for instance, only fell over because the town had cut down all the trees with good root systems, redditor Brysamo said. “My town had a habit a few years back of cutting down any tree that was ruining the sidewalk,” Brysamo said.

The discussion was often edifying, if not always universally compelling. The debate that accompanied this image of an upturned tree, for instance, focused on whether its root system had pulled up soil, sod, or sand (it appears soil and sand, but no clear consensus was reached, if you’re concerned).

For a minor disaster like Irene, Reddit’s contribution was negligible. But there’s certainly potential in the idea. Imagine a similar subreddit for a truly major disaster, or for protests like those organized during the Arab Spring.

The social news site also offers something different from the decentralized cacophony of Twitter or the closed silos of Facebook: the collective brain of its millions of readers, who leap into comments offering advice, context, and, often, help.

Take this post from earlier today, for instance, from redditor TheSixofSwords:

“I spent the morning moving branches, and the thought crossed my mind that if anyone is forever alone-ing or just needs some extra hands to get the debris cleared, then we should summon the reddit task force.”

Photo courtesy of redditor Brysamo