The KDE e.V. president and one of the developers of KDE Plasma, Aaron Seigo, has issued a challenge to Mark Shuttleworth which has remained unanswered, so far.
Mark Shuttleworth wrote on his blog about the people who are making a political stand, in his opinion, against Canonical's Mir display server. He also said the they are a part of a “Tea Party”, which can be construed as an insult, in various parts of the US at least.
One of the first people to react to Mark Shuttleworth's statements (although he didn't named someone in particular) was Aaron Seigo who challenged the founder of Canonical to a public discussion. He didn't respond.
“The message is clear: Mark is willing to insult and demean others publicly, but he is not willing to have an adult conversation about those same matters publicly. “
“This is not the sort of leadership called for, nor acceptable, within the Free software community. It is the sort of behavior that tears a movement apart from the inside,” stated Aaron Seigo on Google+.
It's unlikely that Mark Shuttleworth will answer to this second post, but there a lot of unresolved problems between KDE and Canonical which must be solved, one way or another.