Ubuntu 9.10 Karmic Koala is out. The installation has improved, boot time has improved and overall performance and experience has been revamped.
The next thing would be to try out some tweaks or install some missing applications and support. You can try these out:
Add more software:
Add more software and packages to your package manager and Software Center by using a modified sources list. This gives us options to install unsupported applications, media codecs and applications from third party vendors, applications like Opera and Vuze. For a guide on installing more software in Karmic Koala, visit this post on adding more software sources.
Although the default Ubuntu theme shipped with the Karmic build is excellent, it is a bit dark and does not go with icons of many applications. In such a situation, you can use this theme for a blue look or this theme for a green look. As obvious, these themes have a focus on the color scheme.
Add handy applications:
You can get more tweaks and customizations at this Ultimate Tweak List.