The people at it were clearly American-style liberals though. It was 'we're lefties, and look at how clever we are to think of these signs' rather than a genuine moderate, sensible, centrist movement rejecting partisan two-party politics, as V said. I doubt the whole thing wouldn't have happened if the Tea Party didn't have a bit of a silly public image - you get the feeling the protesters were more about declaring themselves non-silly and making ohsoclever ironic internet jokes rather than actually making an argument in favour of immigration or taxes or whatever. I saw interviews with the participants, they barely even knew if there were elections in their districts. Plus the 9/11 truthers were there, so guess what? Both sides have their morons. 9/11 truthers and ignorant hipster twats holding ironic signs are just as mockable as birthers and old ignorant twats holding passionate badly-spelt signs.
No doubt Trapt/rio will be along to rage in a minute about how the left in America is reduced to mocking the seriousness of politics under the leadership of a pair of tv clowns. Hard to disagree, wherever on the political spectrum you come from.