The headline text in that screen grab from the Seattle Times is trying really hard to be metadata and connect these two items based on shared topic coverage. Turns out, though, that the character string ‘3D’ can carry different meanings in different contexts, so matching items based on common text isn’t the slam dunk certainty that the UI folks from the Times would like it to be. If we want reliable indicators of relationships between items, we’re going to have to do some information modeling work.

Headlines from Seattle Times,
Nation & World, Feb. 20, 2013
Nation & World, Feb. 20, 2013