Amazon offers credit on Metroid: Other M, Assassin's Creed: Brotherhood, more

Amazon's list of
bonus offers is a good resource for people who like to receive free money for basically no reason when they pre-order games.
Metroid: Other M is among the latest to be bundled with Amazon credit as an incentive, to the tune of an extra $20. Other notable recent additions include
L.A. Noire,
Assassin's Creed: Brotherhood and
Disney Guilty Party (all three offering a $10 credit)
Amazon is continually sneaking new offers in among the ones like
Halo: Reach and
Call of Duty: Black Ops that have been available for some time. Which kind of makes sense, since new games continue to be announced even during the pre-order period for other games.