If you're like me, you have to deal with multiple oses for work and don't have time for some X versus Y war. My machine runs Vista64 and I'm one of those people that cannot wait until Windows 7 is finally released. Some of my applications (ok, some old games like MAME) don't run well on Vista, so I was delighted to hear that that the same relaible tech that drives my virtual servers will emulate Windows XP.

Legacy applications are what built the original mainstream Windows 3.1x which could run DOS apps, something the competitors like the IBM PS/2 or the Apple Macintosh couldn't.  Windows 95 ran 32 bit applications and 16-bit applications, allowing old apps to share memory w/the newer ones. Vista admirably does run 32-bit and 64-bit apps fine together, but suffers when trying to simulate all the old registry and XP hackery. Windows 7 solves this by doing it XP style.

If you are new to virtualization, check out the free (though a little dated) Virtual PC or if you feel adventerous, Virtual Server. You can run Linux, DOS, old Windows and yes, even Hackintosh... and it all sits as a file on your machine. As an avid virtual machine (VM) user myself, I find the real McCoy (actual physical hardware) and the virtual machine difficult to distinguish, especially when I use remote desktop to connect.

If you are waiting to buy a machine or plan on building one yourself for Windows 7, you can get started now. I recommend you make sure your processor supports the VT (Virtualization Technology) instruction set. There are a very large number of high-end CPUs out there that are missing this feature. Most applications run fine, but this extended set will makes the XP feature (and any other VM you throw at it) fly.