I don't understand why everyone is screaming that this is the end of .NET, are we going to build webservices using javascript, workflow systems using javascript? that's insane..

Microsoft invested lot's of money into building the parts of .NET. And I don't see them push out javascript based frameworks and solid tools to do this before the release date of windows 8. I don't know what the development of Silverlight 5 costs, but I assume it isn't that cheap to let it run and throw it away, because of html5.

The story of building these small apps in html5/js instead of silverlight isn't that bad. This probably has a larger range of supported devices than silverlight or wpf (can) have. I would not be supprised if you could just build silverlight or wpf tiles if you wanted, which might in some cases be more reasonable than building it in html5/js. But if you build them in silverlight, than they won't be supported on other devices, like the ipad or android tablets.