Kevin, of CollectiveIntellect.com, comments:
When the pollsters first missed the mark in Iowa, the social media research company I work for decided to see if the blogosphere was as wrong as the traditional media. Using a more primitive version of our current methodology, we were pleasantly surprised to see that a measurement of blog sentiment and activity would have correctly (if narrowly) predicted an Obama win. Our theory as to why this is: people so engaged in the political process that they publicly blog about their favorite candidates could fairly represent those who are engaged enough to vote in the primaries and caucuses at all.
You can see the results for five Super Tuesday states here.