I was under the impression that the Debian team is much larger than Cannonical. This is why they have always said that they could not do what they do without Debian. The biggest problem with a rolling release is that you constantly have to reboot the server to apply kernel upgrades, which you have to do less with LTS (though the first 6 months after the release it feels like a weekly chore).
I am sure they are larger, but I highly doubt they invest as much time (full-time), and do it as cohesively as Canonical. That's without factoring in all of the volunteers and other unpaid contributors. Debian has a notoriously slow, bikesheddy decision-making process, also.
Whether you like them or not, Canonical is probably going to be able to do this a bit better. They really can't afford to not do it any better. The mindshare difference is particularly staggering right now. This isn't a direct measure of mind share, but take this as an example:
Ksplice [1] lets you do that. For a while they had very limited support for it, but I just checked and they seem to support Ubuntu on the desktop as well [2]. Once this comes to the server edition and/or is bundled by Canonical, using Ubuntu would become much smoother.
