One of the things that internet/web enables is to make low-cost data collection and analysis mostly a computational question. Add in the idea of "wisdom of crowd", then you have the making of PARC's inference engine technology - if you would allow for a gross simplification.
What the inference engine is good at is to identify items that may be linked in ways that is not always obvious. My favorite example is how the inference engine easily cracked the heavily redacted story on the location of a CIA agent's first assignment in How to catch a spy.
But the same technique can also be used to identify emerging trends (chatters) on a specific topic. So, I used the Inference Engine to look at the top terms associated with the Sonia Sotomayor's nomination process to the US Supreme Court at Sotomayor Web Chatter Index.
And, indeed, it is interesting to see what are the top ranking terms associated with that process and how it points to specific concepts that come in and out of favor in the web crowd.
Finally, it may be worth noting that the same technique can also be applied to data corpus beyond the visible internet. For example, eDiscovery in legal proceeding is a space where this capability would be very helpful by expanding beyond simple keyword search to a more nuanced understanding of how information linked to each other.