I just upgraded my Ubuntu to 6.06 and it was quite painless. I only specified the Dapper Drake repositories and ran "apt-get dist-upgrade" and after 2 hours I had a new version of Ubuntu. Why can't Microsoft do something like that? I know... they don't have a packaging system with dependencies (they have a DLL hell instead).
The next experiment was to install Sun JDK. So I added the multiverse repository and tried the announced "apt-get install sun-java5-jdk" and it worked! Only one click-through text license and the JDK was there. Running "java -version" but surprisingly showed 1.4.2. Well, I realized I needed to get rid of the GCJ (piece of cake with the Synaptic package manager).
There's no "apt-get install netbeans" yet (hopefully there will be one soon now that Sun JDK is in Ubuntu). Installing Sun Studio on Ubuntu was quite painful, I got the bz2 package from java.sun.com, but it contains only rpm packages. I tried an ugly hack - installed the rpm manager and did rpm -Uvh \* --nodeps --force on the rpms of Sun Studio (yes on a Debian-based distro). Well, it worked for most of the rpms :) Last thing I needed to do was to specify the JDK_HOME environmental variable to make Sun Studio 11 work.
I really look forward to next version of Sun Studio which will be based on 5.5 - Sun Studio 11 is based on 3.5 and it's a really big difference. But the C/C++ pack for NetBeans already shows the direction where Sun's C/C++ tools are heading - it's just so easier to work with the C/C++ pack based on 5.5 than with the original Sun Studio, at least for me.