Now that AdMob is part of Google we're not getting the great monthly data and reports that we used to see from the company. But Google has just put out some new data on impression growth. The headline (literally) is that AdMob is seeing 2+ billion ad requests per day (on a global basis).
Google previously said that it had a $1 billion mobile advertising run rate. I did a quick analysis of how that billion might break down, assuming that mobile ad revenues were distributed along the same lines as paid-search revenue generally speaking.
IDC's revised US mobile ad numbers show Google as totally dominant over the rest of the field in terms of market share.
These figures below include search, which is 56% of mobile ad revenue in the US according to the firm. Almost none of the competing mobile ad networks and platforms have search ad revenue, which is why it's so lopsided in Google's favor. Just looking at display the IDC numbers look somewhat more balanced: