Google announced last week the launch of their new AdWords ad rotation option that allows us to optimise for conversions.
Previously Google allowed us to Optimise for clicks and Rotate ads more evenly.
The previous option of showing the ad with the higher clickthrough rate was an unpopular one here, as it was never the case that the highest CTR would guarantee the highest conversion rate. The Rotate more ads option had been a personal choice of mine in the past, and keeping a table comparing the clickthrough rates and conversion rates, making the necessary ad changes and pauses over a given period.
This new setting, Optimise for conversions is available when you have Conversion Tracking in your account and will use your Analytics data to determine which ad is most-likely to convert. Clever.