The two Ubuntu groups have decided to kick Artur Rona out of the Ubuntu development community for at least two years, according to this mailing list post. This Polish developer had been responsible within the Ubuntu community for handling merges, syncs, and security updates for some packages.
As to why Artur is being expelled appears to come down to in-fighting and "general impatience and rudeness."
But now there are some Ubuntu members questioning this action since they weren't even aware of the problem and the Ubuntu Community Council and Ubuntu Developer Membership groups had discussed this situation in the dark off of any public lists. Or as Scott Kitterman says, "I'm not at all comfortable with secret trials and expulsions...We place a great deal of trust, responsibility, and power in the hands of the DMB and CC and I think that being transparent on this issue within the membership of the project is an important balance in this type of case."