I'm going to be the odd one out here. When I cook burgers, I usually find the fat is completely rendered at 160*-165*, which is what causes the burger to swell. If I wait until the burger reaches that temp to take it off, then it's still going to climb 5* or so and the end result is a burger that is overcooked. I actually want to take off the burgers before it reaches this temperature, i.e., just before it swells. If I take it off before it swells, then those divots remain in my burgers. Your mileage may vary depending on your cooking method (and also your preference), but this is what I typically find with mine.
Incidentally, E. coli is killed at 155* (with no rest time needed; we're told to bring ground meat to 160-165* to give us some leeway). I generally shoot for 150*-155* as I know from experience my burgers' IT keeps rising about 5*. Note that the rest time is important. If you rest your meat longer, you can reduce the temperature. For instance, cooking and holding your burger to only 145* for 2 minutes will kill 90% of the E. coli, and for 3 minutes will kill 99% of the E. coli. We want to kill more than 99%, but you get the idea.
I guess the short answer is "no, I don't dimple," but I'm certainly not against it.
