Perhaps I was naive thinking the WinRT API would be similar to .NET, but Microsoft could have made it much, much simpler for current .NET developers to start working with WinRT.
My biggest gripe is that WinRT seems to be 100% focused on mobile/tablet platforms. My laptop has Windows 8 and I spend all of my time in the desktop, away from apps. Why? Because there's a lack of "real" applications in the Windows 8 Store. Writing system utilities for a more technical audience is almost impossible. They replaced the excellent System.IO namespace with the Windows.Storage namespace, which doesn't give you access to much of the computer's actual storage [1].
Hopefully I'm wrong and someone posts a reply with an easy way to search through the computer's files and folders, but I'm not getting my hopes up.
[1] http://msdn.microsoft.com/en-us/library/windows/apps/windows...