http://news.bbc.co.uk/hi/english/world/africa/newsid_1600000/1600250.stm

For at least several years now, Bin Laden and his supporters and allies have sought to radicalize the Islamic community in Northern Nigeria, pushing for more and more states to adopt Sharia, and willfully pushing Nigeria towards a civil war.

Al-Queda is exploiting Nigeria's notorious chaos, corruption, and crime - telling Muslims that all they have to do is adopt Sharia, turn Nigeria into an Islamic state, and peace, law and order, and prosperity from the nation's oil wealth will be their reward in a more just society. In this case it's a more earthly pitch than the promise of 72 virgin in Paradise, I guess.