When insider publications raise questions about base voters, they tend to talk about it as if what matters are whether highly plugged in highly informed base voters are going to be excited or stay home. But the real issue isn't whether someone like me stamps my feet, writes furious blog posts, and refuses to go push the button with Arlen Specter's name next to it, it's whether the new and younger voters who voted for Obama, some of whom are plugged in and some of whom aren't, just don't bother. It's whether activists bother to register new and changed location voters. It's about voters who, for whatever reason, don't always bother to vote show up.
There might be some pissed off anti-Obama Lefties - and good for them! - who choose to stay home, but much more important are the larger number of people who need a bit of encouragement to get them to the polls.