Editor in chief, The Next Web, France shares xkcd without attribution
plus.google.com
plus.google.com
Honest question. So, what?
Provided I don't make/imply a claim of authorship—and in this instance he clearly hasn't—I simply don't perceive a duty of attribution when I'm sharing things to friends.
The claim here seems to be "as Editor-In-Chief of a site dealing eminently with the Web, he should know and follow it"; but indeed - trying to stir up a storm in this very tiny teacup sounds forced and sensationalist (there are much more interesting cases, such as The Oatmeal versus that "fun-something" site).
I don't attribute either. I don't need to because I only post a link to the original. XKCD is best delivered with the title and hover text which is impossible to do correctly on G+