I think the biggest lesson of 2012 is that the people are much better connected now than they ever have been. That means that bold manipulative lies don't work, because they can be exposed, quickly, by networks of people that voters trust. In the past, politics was totally centralized. Like everything else, it is not centralized anymore. We have fact-checkers, we can listen to them, and now apparently enough people do that we can enforce a certain discipline on our candidates.
Would we even know about Romney's 47% comments if Twitter, YouTube and Facebook weren't as prevalent as they are today? It's a new world. And the people who hate it are going to come gunning for it, hard.