New Line Cinema ran a test on the ad-supported Greystripe mobile game network.

Results are interesting:

Mobile advertising on the Greystripe network led to ignificant increases in awareness of and interest in The Golden Compass” film. The ads were not only highly noticed by the overall audience

“Mobile Ad Awareness increased by +59.7 percentage points — but respondents exposed to the ads also exhibited a 19.3 percentage-point increase in awareness of the film’s title.
Furthermore, ad exposure resulted in a +9.5 percentage-point increase in interest in seeing the film among overall respondents. “

Entire study here