My existing computers run my applications just fine. Driver support for Linux and Windows XP is excellent. Performance and stability are very good.
To run either Vista or Windows 7, I would have to completely upgrade/replace my current hardware. That's just to run the operating system, not the applications!
Since my existing setup does everything I need it to do and does it well, why bother?
If I had a limitless budget I may be more inclined to accept the completely artificial "upgrade cycle" outfits such as Microsoft try to force upon us, but I don't. The Windows OS is expensive, so if the time ever came that I *had* to buy a new version, along with all new hardware just to run it, then I would ditch Windows completely and stick with Linux.
And if greedy and/or inconsiderate commercial astronomy software vendors stopped supporting (or failed to support) Linux and/or older versions of Windows, I'd be forced to go without computers, which I believe has been done before.
