There is no problem with selling themes. What may be a problem is distributing a theme under another license.
I think it's unlikely they'll do anything about this as legal action would be detrimental to their community; meaning that this won't be decided unless someone who receives a non-GPL'd theme contests it. This doesn't preclude Automattic/Matt from stating their view and raising a bit of a fuss as you put it in the interim.
To be clear - I'm neither a fan of the GPL, a lawyer or a WordPress user so I don't know whether Automattic is in the right and I'm indifferent as to whether or not they are.
I think it's unlikely they'll do anything about this as legal action would be detrimental to their community; meaning that this won't be decided unless someone who receives a non-GPL'd theme contests it. This doesn't preclude Automattic/Matt from stating their view and raising a bit of a fuss as you put it in the interim.
To be clear - I'm neither a fan of the GPL, a lawyer or a WordPress user so I don't know whether Automattic is in the right and I'm indifferent as to whether or not they are.