I do not here much about the advanced security UAC provides W7 and Vista with. I guess that means that everybody, including MS, finally understand that Windows cannot be secure, even theoretically. However, it is good for a server to be secure.

WinTR apps can, at least theoretically, be secure.Thus, they may be welcome on the server and Metro is likely to be required to launch them.

I do not say that much or any server functionality is WinRT based in this release, but that may be the way to go with future server versions.

I also see people running a bunch of extra stuff on the servers, from file managers to web browsers. If that are Metro apps, the security threat will be lighter.