eWhisper - 3:03 pm on Dec 2, 2010 (gmt 0)
I love testing display URLs; and often find very different results based upon different URLs.
I think the first post about testing display URLs here was from 5 years ago: [webmasterworld.com...]
And I've been around here too long; the good primers on testing are 5-6 years old (and still relevant):
[webmasterworld.com...] (supporter forum)
[webmasterworld.com...] (this forum)
I've seen some heatmaps of ads where the display URL is the 2nd most examined component of ad copy behind the headline (people want to know what happens after the click).
Display URL CTR is a component of QS.
It tells someone your domain.
It tells someone where they go if they click.
It's part of your ad copy (think of it as as copy, not destination URL).
It's 25% of your ad.
It's very much worth testing.