Continuing the evolution away from the "avant-garde" editor approach of Slashdot and Boing Boing, the beta version of digg allows community members to flag and categorize stories which they feel are significant. It extends the del.icio.us concept with a quick voting mechanism, but limits the number of categories.
How digg expands the rating and rewarding of better story-spotters is going to be interesting. There probably should be some limit to the number of "diggs" (the currency of this site). To continue my usual market-oriented thinking, a cut of future diggs for a particular story should be awarded to those who flag and tag that story early on.
Spotter: del.icio.us (where else?)