The most notable omissions are Android app compatibility and the new integration of Microsoft Teams.
Windows Insiders can go ahead and download the new build if they are in the Dev Channel.
I wouldnt install it on your primary PC unless you really know what youre doing.

Casual early adopters will be better off waiting until the preview hits the more stable Beta Channel.
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For more on the first Windows 11 preview, you’re able to read more in Microsoftsannouncement post.
