This week facebook announced a new feature in their advertising platform which give people an ability to split test several ads to find the ad that perform best.

The strength of facebook ads is how they are able to target the ads to right audience.
The new feature allows advertisers to have a 1 day test which determines which of the ads performs better.  The ads are randomized based on people rather than cookies and the audience for the test ads does not overlap. facebook reports that they see a 14% improvement in CPA using the split testing.