A lot of the ire within the Debian community about the release cycle decision seems to stem from a "Ubuntu vs. Debian" mentality that only works to the detriment of both projects. In an email to the debian-project mailing list, Shuttleworth detailed why coordinating releases between not only Debian and Ubuntu, but also upstream and other distributions, can only work to better the Linux ecosystem.
"We're already seeing a growing trend towards cadence in free software, which I think is a wonderful move," Shuttleworth writes in the email, "Here, we are talking about elevating that to something that the world has never seen in proprietary software (and never will) - an entire industry collaborating. Collaboration is the primary tool we have in our battle with proprietary software, we should take the opportunities that present themselves to make that collaboration easier and more effective."
In order to meet the upcoming December freeze, Shuttleworth is willing to commit several Ubuntu developers to the Debian project. "If the Debian community is willing to consider a December freeze, then Ubuntu (and Canonical) will commit resources to help Debian meet that goal," he writes, "It means we'll get less done in Ubuntu, but the benefits of having a schedule which could attract many other distributions would outweigh that." He believes other distributions will join the December freeze. He added that if the December freeze is not possible, he's also willing to disrupt Ubuntu's release cycle to make it all work better - but he won't commit to both developers and a change in cycle.
He closes his long email by adding: "This is a good faith offer of help and support in order to reach a tough but noble and achievable goal. It won't be easy, the first time or the next, but it will kickstart a process that will bring dividends to Debian, and to the whole broader ecosystem. Ask upstreams what they think, and whether they would want to participate, and you'll hear a very positive response."
I think this is indeed a golden opportunity for the Linux world to show that by being open, they can collaborate openly to make not only the lives of users easier, but also of distributors and upstream developers. A release cadence is a great idea that fits the Linux world well, and will improve the experience for all involved.