The web just jumped back a decade to crappy old html. XAML is infinitely superior. You can't even extend HTML server-side without writing code :( It's got loads of odd rules. It still thinks everything is an overflowable document when I want to write an application.
The web just jumped back to a kooky little language that's not grown for decades. Javashit.
Silverlight had support for static, dynamic and even functional languages! C#, VB.Net, IronPython, F#. And it's actually fast and compilable unlike javaslow.
(p.s. I don't actually mind javascript that much, but I do think it's pretty poor compared to C#, Python, Ruby, etc. I do actually detest html though.)
A lot of us don't need cross device compatibility. In fact cross device compatibility is pure laziness in many instances as a iPhone optimized web app should look very different to a laptop/desktop browser optimized app.
I'm not really sure where I stand in all this, but I'm not dancing around with joy about HTML5, which I think is pretty basic and ridiculously behind the times. These are features they should have introduced a decade ago.
I also really wish they'd make some way I could use other programming languages in the browsers.