There's a bunch of people saying they should go down to 1 release a year.
There's also a bunch of people saying rolling release is great.
I agree with both.
There are some stable, important plumbing in the system that always needs to work and doesn't need to be updated all the time. Things like X.org, PulseAudio, Unity features (bugfixes are another matter), Compiz and so on. They need to be kept the same for a year so people can settle in. I've seen so often that I install Ubuntu on a new PC at my friend's house and he's super happy with it, and the next time he turns the PC on he gets a black screen because Canonical decided it would be a great idea to rev X.org or something retarded like that; or all of a sudden sound doesn't work because they revved the drivers - and so on. This should go on a 1-year release cycle and, safe for the occasional forced security update, should NEVER EVER update more often. NEVER update for new features.
On the other hand, I'd always like to have bleeding-edge builds of apps like Firefox, GNOME, Eclipse, GIMP, and so on. This should go rolling release.