The conditions, as Sara Robinson notes, are ripening, but we're not quite there yet, and Barack Obama is certainly not an agent of revolutionary change, no matter how many millions of people would wish him to be.

Give it another few years, with the economy worsening, more people losing their homes (or abandoning homes that are worth less than the owner's debt load), and ineffectual Democrats in power continuing to do nothing and pleading that they need 80-20 Congressional majorities, or Congressional unanimity,  before they can even begin to do anything.  The revolution won't happen in 2008, but the conditions are ripening.