I had a recent run in with Ubuntu... 12.04 running the unity interface (Wayland). I ended up being annoyed with it (because of quirks in Unity) and quirks interacting with the nVidia proprietary drivers.
The greatest thing about Ubuntu is the sheer size of it's repository... HUGE. I am a fan of the Debian based Linux distro's, but the overall feel of Ubuntu has made me look for alternatives. I prefer Mint (based on Ubuntu).
Decided to install Fedora instead (no proprietary nVidia drivers installed, graphics are good with noveau) and no issues with my dual desktop...
Overall, Ubuntu is a great distro for people who want to install and use an OS with ease. It is one of the easiest to set up and get running.