I don't think Orzag's plan is realistic just because it requires compromise and today's politicians signing on to tomorrow's decision. We could have different politicians by the time 2013 gets here or the sensible voices of yore might be trapped in a tough primary and have to stop being sensible (See McCain, Sen. John).
Regardless, I think it's a good thing more and more high-profile policymakers and pundits are saying that we need more revenue. People don't like government spending, but don't want to be without government services. Since we can't privatize everything, we're going to have to start taking in more money to pay for it. Reality sucks, but senior citizens living in poverty, roads and bridges that are crumbling, a pay-to-learn education system, and an ill-equipped military will suck more.