Google's update this week of its Webmaster Tools service has introduced click-through rate data for natural search keywords for the first time.
If accurate, this will shed some very useful light on the correlation between keyword volumes, ranks and visits, aligning natural search marketing strategy closer to that of paid search where comprehensive performance data has always been provided by search networks.
Greenlight is preparing a thorough analysis of the accuracy of this data particularly when compared to other sources of data such as Google Analytics
, other web analytics packages and the search volumes provided by the 'External Keyword Tool'. It should make for interesting reading so keep watching this space...