In a previous post, I talked about how AdMob’s move to stop supporting ad mediation layers such as AdWhirl and TapJoy for ad serving was bad for competition in the mobile advertising market, and would push many iPhone developers into having to make a tough choice to stick with Admob or go elsewhere. Now AdMob has gone and acquired AdWhirl, thus changing the developer’s choice from ‘to AdMob or not to AdMob’ to ‘to trust AdMob or not to trust AdMob’.
Despite AdMob’s (sincere, I think) assurances of transparency and fairness, open sourced code and so on, it’s just human nature to be suspicious and look for conspiracy. How can AdMob assure everyone that they do not have a conflict of interest between becoming the biggest ad network in the world and offering a service that helps developers use other ad networks to monetise their apps instead? You can’t be an independent financial advisor if you’re incentivised to offer products from only one bank. How can AdMob be an independent mobile ad broker if it really wants you to use its own network?
AdMob knows that information is the new oil. That’s why they launched AdMob analytics, which already gives them plenty of information about their customers and also rival ad network performance, because advertisers can use it to track ad performance with other ad networks (although it can’t track pricing). But this is exactly the same reason why people will not trust their acquisition of AdWhirl.
What iPhone developers need now is a mediation layer mediation layer whereby the app can switch between mediation layers to serve the highest paying mediation layers’ ads 
Alternatively, AdMob could ensure they offer such great eCPMs and revenue-share to developers via their own ad network that it becomes a no-brainer to use them, mediation layer or not.
