The Inquirer claims that Intel's Core Duo chips are set to see a price drop as of May 28th.
The price of the high end 2.16GHz Core Duo that is a build to order option for the MacBook Pro is set to drop as much as $214 per unit. The slower clocked chips will see more modest price drops ($129 drop for the 1.83GHz chip and $54 drop for the 1.66GHz chip). Also expected is a 2.33GHz T2700 Core Duo processor later this year.
This does not necessarily mean a price drop on corresponding Macs, however. Apple historically has been relatively consistent in their Mac pricing for the duration of a product's lifespan.
Update: Previously posted by Appleinsider.