I think 4ad has a good point here. It's been a long time since I has the same kind of thinking: Shuttleworth won't spend all his money in Ubuntu indefinitely and/or he wants his firm to be financially sustainable over time. They've tried hard to make a living out of desktop market, and it never worked out. Now they cut it and focus on B2B markets. No longer expect Canonical to make innovation for the end user market in foreseeable future.

The way he is expressing his bitterness to the open source community in its Google+ post is telling.

We may expect Ubuntu to drift slowly into the once-in-a-time-popular distribution graveyard.

I think you've nailed it. Every move and announcement screams that Shuttleworth has given up on his ambitions. Which is a pity, because the ambitions themselves were laudable.

It says in this headlined article "We're now entering a new phase of accelerated growth".

Could be the reason.