I switched from Debian to Ubuntu on my laptop, and am 95% happy with it. The 5% is that there's no easy way to report bugs, so I cannot easily contribute to improving Ubuntu.
In Debian, I used M-x report-bug in Emacs, and it was easy. In Ubuntu, the Emacs interface is gone (M-x report-debian-bug sends to Debian), and the report-bug command line program is not integrated into the bug reporting system.
Filing bugs on a web system is a damn pain, and report-bug or its Emacs equivalent is much easier. Sure, some people like the web interface, but others (like me) hate it. If report-bug would send its reports to a gateway that posted to the web system, that would be ideal and would get the maximum bug reports submitted to Ubuntu.