I haven't started learning yet, as I'm still up to my ears converting from VB6/ASP to .NET 4.0. We have 2 tablet applications written in .NET Windows Forms that need updating. They are only used to collect data for upload into the web application, and should be thought of as disconnected modules rather than stand alone applications. With the anouncement of the MS Surface, I think we have a viable platform to use. We want to stay with .NET to share Business Layer code with the web application, and to ease the WCF calls. I'm sure it will take the Army Golden Master program awhile to adopt and provide a secure image of the Win 8 RT OS, so I expect I will have plenty of time to learn to program for Metro and to re-write the applications. I'm looking forward to providing the features my customers need on a platform that they want.
Bruce Clegg