AT&T has revamped its successful YPMobile iPhone app and included local business video profiles and PPCall ads. Previously there had been no ads on the app. According to the press release out this am. The main changes are the following: 

• Tuning in to Video Profiles: Business video profiles found across tens of thousands of category and local geography combinations on YELLOWPAGES.COM and on the YELLOWPAGES.COM YouTube(TM) Channel are now easily accessible from the YPmobile App, giving advertisers another way to interact with consumers while on the go. 
• Pay Per Call Ads: AT&T Interactive's Pay Per Call(R) advertisers now have the opportunity to be featured with their ads displayed at the top of relevant business search results on the YPmobile App. While YELLOWPAGES.COM subscription advertisers already have the opportunity to be distributed across AT&T Interactive's mobile applications, adding featured placement for Pay Per Call(R) advertisers leverages a unique opportunity to monetize the mobile local channel and offer businesses a cost-effective way to connect with mobile consumers.

It hasn't yet shown up (for me at least) in the iTunes store so I wasn't able to test out the video or take any screens of the ads. However PPCall is, for obvious reasons, well suited to mobile handsets and I imagine AT&T/Yellowpages.com will see some nice volumes to their advertisers from the iPhone app. 

Beyond its own mobile app Yellowpages.com advertisers gain mobile distribution through Bing: