I just spent half an hour voting up and down ideas at CitizensBriefingBook.change.gov
I really like our soon-to-be-President's style; I'm sure the Bush administration would find a hundred reasons NOT to put up a website where people can post their ideas (and where other people can vote on them). Heck, I can think of a few reasons why it might not work out, but trying it is a fantastic idea. The best ideas, that pretty much everybody agrees on, should rise to the top, controversial ideas should get stuck in the middle, and the bad ideas should be quickly voted down.
I think this kind of "Extreme Democracy" is the future of politics (but my track record of predicting the future is poor, and I'm overconfident).
(PS: I know nothing about the ExtremeDemocracy.com folks; I just ran across their website googling for the phrase "extreme democracy" because I wanted to see who else was thinking similar thoughts...)