Beating the puzzle at Whysoserious.com/Bamboozle/2l43kjsa892nn2.htm brings up Whysoserious.com/Overture. The site depicts the "reaper" bomb from Whysoserious.com/l_flave2323, but this time with a countdown to 10 PM EDT on July 10, 2008.
 July 10, 2008
After the detonation time expired the website was covered with HA HA HAs and "making my mark..." was displayed on the bomb.
Clicking on "making my mark..." linked to a vandalized Citizensforbatman.org. It was discovered shortly afterward that all websites in the game (excluding sites already owned by the Joker) were "Jokerized," including all of the submissions on Ibelieveinharveydent.com and Gothamcablenews.com.
Some of these sites have a picture of a puzzle piece with a letter on it.
These letters can be put together into the phrase "KICKING AND SCREENING," leading to Whysoserious.com/Kickingandscreening.
(Whysoserious.com/Overture) -- direct link