Stewart's "Restoring Sanity" rally will be hosted at the Lincoln Memorial. There were thousands of people who supported the comedian's idea to have a rally, and "Restoring Truthiness" was at one time rumored to be the name of the rally.
Stewart claims that American politics is dominated by about 20-30% of loud, radical Americans, where the other 70-80% remain reasonable. This is his idea of allowing "reasonable" Americans to be heard.
Colbert's "march" is meant to "instill fear" and he told people to book hotel rooms now, lest their children "turn gay." Stewart said to book rooms now because rooms "may not be available later."
Now, I think this is funny. However, somehow I don't think that serious Tea Partiers or supporters of Al Sharpton will find much humor in this. Given the choice between the Glenn Beck/Al Sharpton rallies and marches and Stewart/Colbert, I will take the latter any day!