Deeko
Lifer
Netflix still uses Silverlight. Its funny I find Flash a nightmare to use, I'm sure its different for everyone.
To be honest, I have never written a Flash application - I have written an Adobe Air application, using Actionscript, and it was fairly terrible too. I do a considerable amount of Silverlight development, and as a developer I think it blows either of them away. However, my background is "traditional" programming, and Silverlight behaves more like a "standard" application than Flash or HTML5, so that could just be me.