There are a few reasons to use Vista and lots of reasons not to. Here are 20 more candidates for the second group from Softpedia:
Are you using Windows Vista? Then you might as well know that the licensed operating system installed on your machine is harvesting a healthy volume of information for Microsoft. In this context, a program such as the Windows Genuine Advantage is the last of your concerns. In fact, in excess of 20 Windows Vista features and services are hard at work collecting and transmitting your personal data to the Redmond company.
Microsoft makes no secret about the fact that Windows Vista is gathering information. End users have little to say, and no real choice in the matter.
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The Redmond company emphasized numerous times the fact that all information collected is not used to identify or contact users.
I don't for a second doubt that Microsoft means this. But that's not the right question: the issue isn't how they use it; the issue is how they store it. If the data are collected and stored in a manner that retains a personally-identifiable character, then either Microsoft or someone who handed it a subpoena (or warrant) could use the data to link an IP number to whatever else is collected. And on this question the article is silent — which means that while this may or may not be worth worrying about, we can't actually tell for sure either from this story or from Microsoft's Vista Privacy Statement (indeed, from the sound of the latter, it does sound as if at least some of the data are kept individualized rather than aggregated). And until we know more, chalk up more reasons not to use Vista.
And here's the chaser:
Microsoft has an additional collection of 47 Windows Vista features and services that collect user data. However, not all phone home and report to Microsoft. Although the data collection process is generalized across the list, user information is also processed and kept on the local machine, leaving just approximately 50% of the items to both harvest data and contact Microsoft. Still, Microsoft underlined the fact that the list provided under the Windows Vista Privacy Statement is by no means exhaustive, nor does it apply to all the company's websites, services and products.
There goes your paranoia again. It’s not like our friends in Redmond or their buddies in DC would ever lose or misuse that information. Nothing to worry about–unless you’re doing something which you’d prefer to keep private.