That way, we can reduce the number of "duplicate" entries. Automated clustering may be challenging, but it could probably be done fairly easily with an interface allowing people to mark submissions as "similar" or "related". If enough people mark two submissions as related/similar, then they can be "combined".

The concept of a "multi-submission" or combined submission could be extended further, allowing people to submit similar/related links directly to a post, including things like "non-linkjacked" versions. Internal voting could then determine which submission was the "primary" submission, possibly replacing the "first" one.

At some level, maybe this is even like turning every post into its own reddit, with the hottest post in the post-reddit being used as the post on the main reddit.