I'd say worse, because every single upgrade (since Warty or so) has broken important functions for me, on every machine. There have been reams of buggy alpha software in core roles: NetworkManager, Compiz and now maybe pulse audio. Every upgrade has screwed up some aspect of X, often font display. I'm always surprised by radical overhauls of aspects of linux I've used for years, rarely with any notification "After this upgrade there'll be a new network interface called...". I've had sound drivers stop working, X fail to start after upgrades (and one infamous update), my home wireless broke moving to Hardy.
This doesn't mean Ubuntu is getting worse, maybe bits are getting better, but I couldn't care less about the exciting new whatever-feature if programs I use everyday stop functioning.
Many problems are not Ubuntu's fault, but upstream: pidgin/gaim has sucked every upgrade, I abandoned Evolution after a few years, I now use mpd/mpc for music because everything else I've tried just keeps getting worse, various "..blah.. stopped working" issues have been due to kernel driver bugs. All not Ubuntu's fault, but the messenger blamed is update manager.
I now dread upgrades, I delay until the support period is expiring in the hope that the bugs have been fixed (to no avail). I've been conditioned against upgrading. Now, I'm staying with LTS until I get new hardware. Then I'll have separate partitions so that I can gradually find the bug fixes and only move real work once everything's resolved. I'll also try other distros, maybe OSes.
After a colleague spend hours getting bluetooth working on Ubuntu, an upgrade broke it. He bought a Mac, liked it, and now the office is half Apples. These are machine moving away from Ubuntu, not Windows. I have a Mac on my desk, as yet unused... They're paying inflated prices for "just works".
So "Just Work"!
Upgrades should not break stuff!