Banshee is a very good open source music player. I think older versions ran on all three platforms, and the latest release 1.6 doesn't run on Windows yet (but they're working on it?) Banshee's very stable and has a rapid development model. I think it or Amarok are the logical successors to Songbird. But honestly, I think Songbird was doomed from the start. Computers are moving away from desktops and monolithic programs to mobile devices and cloud computing. By the time Songbird was a finished product, it would already be antiquated by various internet, music services and since it's built on XUL, Songbird has always been a very CPU/memory intensive program.

Ubuntu is *not* Debian. Ubuntu is based on Debian, but has very different priorities.

Debian supports 11 hardware architectures. Ubuntu supports only 3, and as a result can provide much more polished results.

Likewise, Debian maintains 18,000+ packages. Ubuntu maintains significantly fewer packages, but provides much more polished packages for the ones they do maintain.

Debian has militant standards for stability, often leading the software in their stable release to be a couple years behind the curve. On the other hand, Ubuntu releases an entirely new version of their operating system every 6 months, officially supports most releases with security updates for only a short amount of time, and often includes software in their stable release which has not even been officially released by its developers (such as Firefox 3.0 in the upcoming Hardy Heron release.) I.e. Ubuntu's priority is decisively on bleeding-edge software over stability.

Debian is highly customizable and allows you to choose precisely what software you want to install and how you want it configured; it is easy to see what's going on under the hood. Ubuntu is much more mysterious; it's much more difficult to understand what's going on under the hood and much more difficult to customize and reconfigure, but as a result, is more user friendly and easier to install.

Debian is horizontally organized through an ambitious system of democratic (and highly idealistic) self-governance. Ubuntu is run from the top down by a corporation with very limited democratic participation from its constituents.

Perhaps most important of all, Debian has super strict standards for what constitutes free software. Ubuntu's standards are also marginally strict compared with the industry average, but there is a lot of software that Ubuntu permits to be configured and installed by default through the distribution that Debian refuses to support or will not install by default because they consider it non-free. This has been a long standing source of tension between the Debian community and Ubuntu.

In short, both Debian and Ubuntu are great distributions, but Ubuntu is NOT Debian; it has very different priorities. QED