The Interactive Advertising Bureau and the IHS Screen Digest have sized up the mobile ad market, and have concluded that it was valued at $5.3 billion in 2011.

By region, it breaks down like this: North America 31.4%; Europe 25.9%; Latin America 3.5%; Asia-Pacific 35.9%; Middle East & Africa 3.2%.

“As mobile accelerates its global footprint, it is vital that we measure the worldwide and regional opportunities for advertisers,” said Anna Bager, Vice President and General Manager, Mobile Marketing Center of Excellence, IAB. “This key IAB initiative provides an accurate gauge of mobile market developments across the globe, with the aim of helping our members and the industry achieve even stronger growth through mobile.”

Here’s a closer look at the numbers:

Things are looking pretty good on the search front, as you can see. Google, as you may know has been criticized for its monetization of mobile, though CEO Larry Page is “very bullish” on mobile going forward. Google just announced integration of Google Offers into its Schemer app, so that is another potential source of mobile revenue (assuming Schemer becomes significantly popular, which is a pretty big assumption, admittedly).