Comments have become all but de rigeur on Web sites — assuming you like spending half your life filtering out spam, flame, trolls, and other horribleness. Google’s getting into comments, too, but with a twist.

Recently, the newish Google News Blog announced that a new feature would be rolled out in the US news section. This new feature will allow comments on news stories — but only from groups or people involved in the stories.

To find these stories, look for a little comment balloon on the story listings, which will lead to an individual page for the stories — check this story for an example. The comment, clearly marked as such, is included after the story along with a Google disclaimer. I didn’t see that there were many comments available for stories yet.

There were so many immediate thoughts I had upon reading the announcement it was hard to sort them all out. First was, “Good grief, this is going to be a lot of work.” Second was, “If someone manages to hack this (probably socially) there is going to be a volcanic explosion.” Third was, “How many people are going to take them up on this?”

Looking at the comments in action, I have the same thoughts. I also have the thoughts of “Who qualifies to comment?” I mean, is it exclusively people who are mentioned in the story, or is the circle wider than that? For example, say there’s a story about an allegedly drunk driver causing an accident on I-95. Who qualifies to comment? Only the people mentioned in the story, or does someone from MADD get to add their thoughts? And if that were so, how far out would that go? If the car driven by the alleged drunk driver was, say, a Nissan, would Nissan get to add a comment about its development of anti-drunk-driver technology?

I think this is a very daring idea, but there’s going to be a delicate balance between making it open enough to get lots of comments and making it worthwhile, and keeping control over what could be a flood of comments from everybody and their Aunt Bee, claiming the most tenuous relationship to the story…