There has already been quite some discussion on how to get Windows 7 to run under VirtualBox (bottom line: it works – just install it). Here is a litte add-on to this discussion: Running Windows 7 Beta 1 under VirtualBox on Solaris 10 U5 over a SunRay terminal (exhale….).
Now, since I had tried Vista under VirtualBox, I was not expecting anything (except abysmal graphic performance), but – lo and behold – I was quite positively surprised: the install was complete smooth, and the VirtualBox Vista drivers worked like a charm, once I was using the compatibility mode with Vista (right-click the executable on the mounted ISO image, select Properties and the Compatibility tab, select Vista, close everything and then simply double click to install). Without this trick, the VirtualBox installer would complain about not supporting Windows 7 yet.
Overall performance was pretty much as expected: a lot better than Windows Vista, and about the same as Windows XP. Now bearing in mind that the SunRay system is not exactly targeted at power users for CAD applications, and you will arrive at a the conclusion that Windows 7 Beta 1 under VirtualBox is a logical step from running Windosw XP in the same scenarios to deal with those 7 applications that you just cannot find in open source. If Windows 7 actually came in a freeware version, it could actually be worthwhile upgrading those legacy HDD images. But then, Microsoft has shown over the last few years that they are capable of learning, so I will not loose my hope … 😉
Seriously: if Windows 7 has a similar performance and resource demand profile as the beta versions, it has a good chance of convincing me to attempt another upgrade. Just one thing will be crucial: application backward compatibility.