buckworks - 9:25 pm on Jun 3, 2012 (gmt 0)
Here's one idea for some testing ... Assuming you already own both domains, try creating some test ad groups in AdWords that are identical except for the domain of the landing page(s) and display URL.
Watch the stats to see if the domain variations create any statistically significant differences in how users respond. You can learn something useful either way, whether they do or don't.