Chris Smith spotted one of those ongoing Google AdWords user interface tests on mobile. This one shows the ad with a local extension ad format test. On the left of the ad extension box are three links stacked on top of each other and then on the right is a reviews box.

Here is the picture posted on Twitter:

Ginny Marvin covered a similar test a few months ago and posted about it on Search Engine Land.

So maybe Google is stepping up this test?

Forum discussion at Twitter.