How some packages don't update regularly

I recently had to install a laptop with Debian; but I didn't have powerpc install media for Debian directly available, nor did I have an empty CD-ROM (and booting directly from hard disk didn't work for a reason unknown to me since I had no time to find out).

What I did have, however, was an install CD-ROM for Ubuntu Warty for powerpc. So I installed that instead, then sidegraded to Debian unstable, which I run on all my workstations. That went surprisingly well; but there were a few issues worth noting.

• Ubuntu has something with python. What's the story there? python? Anyway. After upgrading to unstable, I had to remove a whole shitload of python library packages of sorts, which weren't being depended upon by anything I had installed, and which I'm also not very likely to use. Ever.
• There are a few packages that haven't been updated anymore since warty was frozen. As a result, they don't get replaced by the unstable version unless manually updated; Ubuntu packages contain a 'ubuntu<ubuntu version>' after every Debian version (which is sane, BTW), but that means dpkg considers it to be more recent than the 'original' Debian version. Packages that were affected by this: at, defoma, gs-esp, gtk2-engines-smooth, libcompfaceg1, and libpaper1. This isn't an actual problem, but it's something to remember.
• Finally, there were also a number of packages that simply are not in Debian but are in Ubuntu, like pmount; these must be manually removed. And while you're removing it, don't forget udev.

That's it. There's nothing here that a non-experienced user can't fix by him/herself, luckily. It's nice to see how both distributions get along so well...