here's what the central bank has to say:
QUOTE
Higher denomination notes do not cause inflation per se. Rather, it is the excess supply of money in relation to the available goods and services that causes inflation. The benefits of higher denominations are that:
-It would restore to the Naira, the quality of portability which low denomination and high inflation rate gradually erode.
-The circulation of higher denomination notes would reduce the long queues experienced in many commercial banks, as cashiers would spend less time in counting notes.
-The introduction of higher denomination notes would engender efficient processing of currency notes. Processing of high denomination notes would yield higher value of money that would meet the currency requirement of a cash-based but growing economy .
-There would be efficiency in currency movement.
-There is cost advantage in the printing of higher denomination notes vis-a-vis smaller ones.
http://www.cenbank.org/FAQs/index.htmand a pic of the new notes:
