There was a 2004 book partially entitled The Wisdom of the Crowds that argued the collective often makes better calls than the individual. I'd call it the Borg Hypothesis if for no other reason than to prove I'm a Star Trek geek.
We've seen people using Twitter to tap into the wisdom of the crowds.
Thanks to PR and social media guru/goddess Karen Russell, I can point to this post, which examines the response to the new The Jay Leno Show via Twitter. It's a neat idea and you can read the text of the full study that compares offline and online responses to Leno.
We're going to see a lot more of this sort of thing, using Twitter or other social media to understand the public's response to, or chattering about, some issue, program, or person. It's a poor man's version of the Nielsen's, but more than that. It's gives us interesting comparisons with the geeky Twitter types (or Facebook, or whatever the tech-flavor-of-the-month happens to be) and real live people, a sample of the general population.
Methodologically interesting, and even more so when we start to see what these two samples say about some topic begin to merge. That's not gonna happen soon. People who examine polls done by the traditional method of landline phones and cell phones aren't seeing this quite yet, but they will. Twitter and other social media? Very different.
Best use? To see something as a trend before it truly emerges. Google does this with predicting the flu. Searches signal something deeper, in this case the flu, so why can't Twitter and other social media signal something in advance of more standard, traditional methods? I'm thinking yes, that's where it will be most useful.