Google says mobile usage has surged this summer The Local OneBox has put local on the maps (so to speak). In terms of real traffic to real websites it has had a significant impact as a way to generate traffic in local and regional markets. That being said, Maps is still a poor step cousin to the organic search results. When we all have the $100 iPhone is when Maps and techniques to optimize for it will become incredibly important.
Putting Your Small Business On The Map - good ideas by Christine Churchill at SearchEngineLand.