While waiting to see if Google shows anything interesting from a social or media perspective at I/O, I’m seeing a common theme in today’s coverage of online media and advertising: companies are struggling to make ad-based businesses pay off. Indeed, it feels more like struggling than innovating. There’s no one model for success in interactive media, but it does feel like Flipboard should be able to offer a pretty desirable ad marketplace and share more than 50 percent of the revenue with premium content suppliers. Of course, while Flipboard is one of the new new things in tablets – and tablets desirable platforms for brand advertising – its user base is too small for very refined targeting yet. Hearst has turned to Pubmatic to cobble together a private marketplace – I refuse to call it an exchange – across its brands. Wait, it’s 2012 and this is the first time Hearst has enabled advertisers to buy audiences across titles? Portals and ad networks have been doing that since the dawn of the Internet. And, lucky for Facebook, some advertisers are increasing their spend, even though they still can’t measure results. That sounds like an opportunity for analytics and services to me.