Paul Thurrott's Morro Review.

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A precis follows for those who haven't got time to read the article.

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Final thoughts
There's been a lot of interest in Morro/Microsoft Security Essentials and I think even the beta version of this product will prove quite a hit with users. It's free, effective, lightweight, and quiet and is, in other words, exactly what I'm looking for in a security solution. And it comes with no strings at all. As long as you're running a genuine Windows version, you can install this product without worrying about up-sell advertisements, yearly renewals, or other silliness. And you can do so on as many Windows-based PCs as you own. I'd like to see it just included with Windows, but what the heck: Free and easy is the next best thing. Microsoft Security Essentials is highly recommended, even in the public beta.
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