A decrease in those wanting the 72 virgins.

Times online has this:

"THE leader of Al-Qaeda in Iraq, Abu Musab al-Zarqawi, is attempting to set up his own mini-army and move away from individual suicide attacks to a more organised resistance movement, according to US intelligence sources.

Faced with a shortage of foreign fighters willing to undertake suicide missions, Zarqawi wants to turn his group into a more traditional force mounting co-ordinated guerrilla raids on coalition targets."

via Powerline