Microsoft has announced that the little cross-platform, cross-browser cousin of Windows Presentation Foundation will be called Silverlight. This technology which was first announced at PDC05 was codenamed "WPF/E".
Tim Sneath has the best list so far of the features and power of this "Flash killer" technology. Microsoft doesn't ever call Silverlight a Flash killer, but the overlap in feature set is so large, that it cannot be viewed as anything other than a direct Flash competitor.
Tim Sneath mentions a secret number 10 feature on his list:
"Ah... #10. I can't reveal this yet - there's a big surprise up our collective corporate sleeve that will be announced at MIX. I hate to hold back on you, but anticipation is part of the pleasure, as my mother used to tell me as a child when I was waiting impatiently for Christmas to come!"
"As I mentioned, this Silverlight announcement at NAB is only part of the story, the rest will be unveiled at MIX including details about how Silverlight is a core component of Microsoft’s broader .NET platform."
I commented previously on Robert McLaws' blog that I didn't think that Microsoft wasn't going to release a lightweight crossplatform CLR for Silverlight programmability. But I also speculated that Microsoft was working on a bigger crossplatform CLR based on the .NET Compact Framework.
What I am pretty sure about, is that Microsoft will announce ASP.NET controls that will allow you to very easily integrate Silverlight on your web pages and to expose dynamic data as XAML to Silverlight controls. I.e., AJAX on steroids UI-wise.