Windows Live Folders sound pretty handy, however I'm not sure if I'd ever find a use for them. I'll sure try and think of one though.
An interesting side point is the way they describe their compatiability:
Folders work well on any Windows or Macintosh computer with Firefox 1.5 or higher, or Internet Explorer 6.0 or higher.
Interesting that they've listed Firefox before IE there.
Unfortunately, the beta isn't available in 'my region'. The beta is limited at the moment and will be expanding over the next few months - more info available on the team blog.
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