Matt Mullenweg and Chris Pearson do not get along. I'll refer to Siobhan McKeown's chapter in the WordPress history book on Thesis for those that want to learn the specifics.
Last year, Automattic bought thesis.com from a third party. The issue was brought to light because Chris Pearson attempted to get the domain back by claiming copyright over “Thesis”, which he lost. The decision was handed out last week.
According to the report, Automattic bought the domain for $100,000. It now redirects to the ThemeShaper blog.
This is a tough one to see any other way than a huge “screw you” from Matt Mullenweg to Chris Pearson. It looks like a $100,000 bitch slap. It's a petty and ridiculous waste of money; Matt won this battle long ago. And it makes this tweet by Matt Mullenweg even more hilarious.
I don't know any more details and I don't really care to. But Matt has a lot of explaining to do if he intends to take the high road here.