By reading between the lines of the MSDN link provided below and filtering out the blatant marketese (which leaves almost nothing), it appears that WindowsFx is the DotNet platform with extensions specifically for WindowsVista. At least, that's what I think it means. Clarity and directness aren't Microsoft's strong points, and the sheer desert-like absence of interesting content caused me to doze off and lose my balance whilst reading the article. As my chair tipped backwards I struck my head on a coffee table. Therefore, I'm no longer confident that the resultant brain damage isn't causing me to misinterpret some of the fluff as content.
Apparently, some features will be back-ported to WindowsXp (e.g. WindowsCommunicationFoundation , "Indigo"), but others such as WorkFlow technology will probably not.
See http://msdn.microsoft.com/windowsvista/about/#winfx
According to the above -- and using the bullet points handily provided as an outline by the original author of this page -- WindowsFx will be based on the MicrosoftManagedCode programming model, which is supposedly more collaborative and more tool-friendly than (presumably) something that is less collaborative and less tool-friendly. It is not explained what "tool-friendly" means. Also, WindowsFx will eliminate common programming errors such as buffer overruns, and a core customer will become the designer. Or something. You can read the article yourself. I read it, and it seems to suggest that Microsoft is prepared to rearrange the furniture and claim it's a new house.
In terms of InformationSecurity, InfoCard will be included as a WindowsFx component for IdentityManagement. More at http://msdn.microsoft.com/winfx/building/infocard/default.aspx
MicrosoftWay of describing WindowsFx
Note historically MS has been observed to pull/change their posted information on products. But It is still useful to examine what has been said at the time about their upcoming offerings.
WindowsFx is:
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