Here's one i've taken since getting my MkIII.... do you all find that having an IS lens helps? This was with the 50 f/1.4 i believe. I definitely need some practice to reduce the blur on the subject.
Yes, I have found IS helps. Unfortunately I've yet to get a shot I like with the IS on - not the fault of the IS. Although the shot of Rubens above was taken with the 70-200MkII, which I remembered to set to IS mode II for panning, I forgot to turn the IS itself on!
As for technique, I have found the following helps: I keep the camera as firmly pressed to my forehead as I can with my elbows tucked in under the camera and I turn at the hip. And of course practice practice practice!