A week ago I installed Ubuntu 9.10 (Karmic Koala) on my "new" laptop, my company was throwing it away because it was old, and I didn't think much of it. One thing that stood out was the network manager, it was a breeze to get it to work. The other thing was the new load screen and login screens looked really cool. These two changes may only be superficial but this version seems really polished.
I've written before about this: Add language and import translations through profile in Drupal 6 (give it a quick read!). Why I did that way before was due to a bug, or maybe an error on my behalf, in earlier Drupal-version that made the imported language overwrite english. So that english was impossible to to switch to or recover.
Something I discovered by accident. The array() constructor allows a comma (,) after the last item. This helps me and saves me time by avoiding bugs. I'll show you...
At work were developing sites almost exclusively in Drupal 6, except for our own self developed E-business solution. Most of our site are in swedish, so I've found a way to add swedish and import all the available .PO-files. I do this in our own installation profile.