This information is outdated! See Mobile Ubuntu Colinux Setup for more information, even if you're not using a "mobile" setup ;-)
In the last years colinux became one of my most valued tools for cross platform software development. Colinux is a user mode linux, running as a Windows process. This way you don't need to dual boot anymore. And while other virtualization techniques exist, colinux has some advantages that makes it my top choice.
The last couple of days I switched to Vista on my workstation. Getting colinux to run was one of my major concerns and one of the reasons why I will have to wait before I can use a 64 bit Windows. After a little research on the web I found out that the tuntap driver that is bundled with the colinux 0.8 snapshot will render a Vista installation unusable. So at first I installed colinux without networking support. Then I downloaded the latest openvpn beta and installed the tuntap driver from their installation package. But when I booted into colinux, I couldn't get the network to work. On shutting down colinux Vista even bluescreened. So tuntap is not the way to go (yet).
My next attempt was to use winpcap networking. I managed to get the network up and running, but I had some strange connection problems when connecting via ssh to my colinux. Somewhere the ssh just timed out the connection. After a little experimentation I found out that I could open a tcp connection to the colinux and could even send data to a running netcat, but I couldn't get any data back.
Then I checked if the problem still existed when I used the Microsoft Loopback Adapter in a setup very similar to this colinux networking howto. Surprisingly the network was not only faster, but also very stable. I still don't know why the winpcap solution didn't work reliably over the real network device - connections from/to outside my Windows box work without problems.
After setting up colinux with cofs as my cross compilation toolchain, I was ready to use Vista as primary devlopment platform. So far I'm quite impressed. Vista is the first Windows where I can easily work as "normal" user, entering the administrator password only when I need more access. This is a big security plus.
Thanks to the user account protection old programs like teraterm still work. It took some time until I figured out why nothing changed when I was editing the teraterm.ini file in the "C:\Program Files\" folder. Since teraterm opens this file writable at startup, Vista silently set up a copy of the file in my local user account folder. This way you can edit setting files for legacy programs without needing superuser privileges.
While setting up Visual Studio 8, I had one more encouter of the third kind with rights management. To make debugging easier, I'm inserting information about my classes in "..\Microsoft Visual Studio 8\Common7\Packages\Debugger\autoexp.dat". I edited this file as superuser, since Visual Studio doesn't need to write to it. But nothing happened. Then I checked the file permissions and it became evident that the file was not readable by my user. Changing the permissions fixed this problem, too.
Now I'm up and running and still quite impressed by Windows Vista. If Vista shows the same progress that Windows XP showed during it's lifecycle, it will become a nice operating system for software development. Um, and yes, it was only a few years ago that I preferred linux for my daily work - but back than Visual Studio 8 wasn't available, which is still my killer application for C++ development.
An updated article on a Mobile Ubuntu Colinux Setup for my laptop is available.