Google is currently sending invite emails to some publishers, to give AdSense for Mobile a try. Part of the email reads:
As part of our efforts to develop new and improved AdSense products for our partners, we will begin a limited beta test for AdSense for mobile. AdSense for mobile allows publishers to monetize their mobile websites through the placement of targeted text ads. Publishers can take advantage of the fast-growing mobile advertising market and benefit from our targeting technology.
I can't wait to hear some feedback on this.
There is currently methods for AdWords advertisers to create mobile search ads, more on that here and from AdSense over here.
Forum discussion at DigitalPoint Forums.