Google: Geographic Performance Reports
Adwords advertisers have a new report at their displosal. The Geographic performance report provides insights into how impressions, clicks and conversions are distributed geographically - all the way down to the ad group level.
The Geographic Performance report gathers approximated Country, Region, Metro, and City data and calculates them on a daily basis at the account, campaign, and ad group levels. Metros are currently based on Designated Marketing Areas (DMAs) as defined by Nielsen Media Research in the United States.
Data for the new Geographic Performance report is only available from May 27, 2007 and will be aggregated daily to ensure accurate counts.