Here's my rational[ization]. Of late, Ubuntu has been aggressively pushing into the mobile world taking aim mainly at tablets and smaller computers. This is evidenced by strong touchscreen support, a revised interface to handle lower resolutions, and the direct proclamations of one Mr. Shuttleworth: Canonical mage. Since it's a different system, it is a competitor to MeeGo, though perhaps not a bitter rival in the scrutinous eyes of the community.