Sure Mark talks the talk. But Canonical does not walk the walk.
Point of Fact: Ubuntu jumped at the chance to support LibreOffice instead of "trusting" Oracle to play the role of good corporate shepard. For him to be critical of LibreOffice now is hypocritical.
Point of Fact: OpenStack's contributor agreement does not require copyright assignment. Eucalyptus's contributor agreement does. Another situation where Ubuntu( under Mark's leadership..leadership with veto power) has chosen to support the project that does not use copyright assignment to shim up its business plan.
Mark can talk and talk and talk about how important copyright assignment is to correctly leverage business interests to take open development to a new level. That sure sounds nice. And I bet when you hear him talk in person, his personal charisma really makes it a compelling argument.
But, look at the track record for Canonical and Ubuntu with regard to how they chose to interact with companies that are doing exactly what Mark says is needed. They shun them. Given the first opportunity they'll jump to supporting a competing codebase that does not require assignment.
This is classic "do as I say not as I do" podium posturing. If Mark, with his very strong beliefs on the matter, can't seem to drag Ubuntu into a direction to "trust" Oracle or Eucalyptus when given the choice between those corporate, copyright assignment requiring entities, and competitors with more community oriented contributor agreements which do not assign copyrights...then why on Earth would Mark expect anyone to pay attention to what he is saying? If he's going to talk the talk, Canonical needs to walk the walk.