Mark today in your calendars because USA Today's headline just made it official: "The debate's over: Globe is warming." My first reaction was astonishment. I kept scanning their website for other up-to-the-minute revelations. What's next? Are the Beatles really about to break-up? Is the Berlin Wall really going to come down?

But my second reaction was more optimistic -- and less sarcastic. I shouldn't scoff at USA Today's belated recognition as much as I should marvel that a tipping point is happening right before our eyes. The real news here is not that the debate is over -- it's been over, of course, for quite some time -- but that USA Today and other media like it have finally awarded a TKO to climate scientists and greens.

As it turns out, USA Today's conviction is because big corporations, utilities, Republican governors, and even religious groups are now demanding action on climate change. There really is increasingly broad-based recognition of the problem. Still, it's more than a little annoying that media evaluate critical issues based not on the overwhelming scientific evidence, but rather on the proclamations of Arnold and a few CEOs.

But on the other hand, if even USA Today says there's a consensus on climate change, then we're just about to arrive in a brave new world where we can actually begin to do something about it on a large and systemic level. Hold on to your hats: next week we'll find out that burning gasoline warms the atmosphere through something called the "greenhouse effect" ...