How would one create fancy UIs in .NET, with glossy buttons and smooth animations? You can point me to 3rd party frameworks, but I would like to understand the technical details also.
There's a free toolkit called Krypton ToolKit that has some nice glossy controls.
I hope somebody else posts about where to find out about the actual technical details, as I don't usually go that deep into that sort of code.
WPF is supposed to eventually replace Winforms. Some of what you learn with WPF is transferable to Silverlight as well.
I find .NET to be overkill for a lot of those things, especially for AJAX stuff. I'd learn to use jQuery or even go directly to the Prototype library (check out scriptaculous).
As far as glossy buttons, get a great designer. If it's a pet project, you can find some great photoshop tutorials out there. But, if it's a real deal project for a client, sink some money into a rockstar designer. It'll make your life that much easier.
Or, even better, don't use a non-standard GUI toolkit or methodology. If there is something I can't stand in software is the over use of skinning and styles to make things look better that the cost of usability.