There's public betas. Generally, you pay MS a few bucks and get a version of windows close to the release date. That's what I did with XP and got the RC1 and RC2 for $20. Other ways include getting versions as a developer, i.e. you're a subscriber to MSDN. Another way is as an OEM. You get some Microsoft betas if you buy a certain number of OEM versions of Windows over time. And yet another way is to be on the IT staff of a large business. The Microsoft sales dept. will give you access to beta software to test it out, give feedback, etc. and hopefully sell the final version to your company. I believe these are a few of the ways that you can get beta versions of Windows without actually knowing somebody at Microsoft personally. There may be others.
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