That's assuming the ecosystem holds together and the warmer temperatures don't begin to cause massive die offs of sensitive plant and animal species. That's also assuming we don't kick off some kind of dangerous feedback loop such as destabilizing methane clathrate deposits or something similar. Are we willing to take the risks? I'm not.

Though I'm not a climate scientest, I'm sure if we had one here they'd agree that ten degrees farenheit is an absolutely MASSIVE change in global temperatures. To say that it would be livable is incredibly naive.