A WebmasterWorld thread has Google AdSense publishers saying they have noticed their mobile earnings have increased nicely.
They also compare click through rates by phone versus tablet versus desktop. Since I just added ads to our smart phone templates, it is hard to compare any of these metrics but I did post some stats over here showing tablets have more than two times the click through rate than desktop or mobile devices. That stat seems to be the norm - others are reporting similar findings in the thread.
But many are saying they earn more from mobile and tablet users than they do from desktop users.
You can access this report in AdSense by going to the "performance reports" and clicking on the "platforms" link on the left. My RPM is highest with tablet users but lowest with high end mobile users. You?
I believe the commenting engine below allows you to attach screen shots.
Forum discussion WebmasterWorld.