There is so much more you can do with Silverlight/Flash than you can with HTML 5. I'm not even sure why they're mentioned together.
WPF being dead...I can kind of believe it. It's been around for almost 4 years now and it still hasn't really taken off. I like it, and it makes drastically changing the look of standard controls extremely easy, but for most developers that's not enough of a reason to move away from WinForms.