I have a Vista Business 64 and a whole array of trouble: it is not very tolerant when it comes to drivers. If you think about an upgrade you better check the support page for the hardware you think of. And do not think of :-) buying 'last-version-top-of-the-hill' hardware, since there are little chances to have from the very beginning vista 64 drivers. The 64 version is design for stability, so it is more suitable for a production environment, where you mostly do critical security updates for OS. In a development environment you may try to install new development tools, and you can run into trouble with your 64 version. Eg: Adobe Flash Player does not have a 64 version. On linux you are doomed, on Vista I eventually found a hack, so now it does not annoy me every time I visit a site relying on flash player. Summing up: - If the hardware is not on the market now, don't by 64 'just in case'. - If you software environment is subject to frequently change, don't by 64 because it is 'cool'