Telling the truth, all these years of programming, I was certainly awful in UI. All the forms or pages were full of unindented user controls, no images, no colors and nothing of eye catching materials.
Threads were always a concern, and I was very helpful to the teams I was working with, by my thread managers even on UI threads. BUT I was very stupid on UI :(
I'm really confident now by WPF :)
Even my first try on WPF was an amazing UX. The gradient brushes, the way they render, glass effects and the powerfull control and data template system. These all will change user taste and I can say even the way applications are thought.
*Note: If anyone is intrested in the code/project files, pelase leave a message and I'll post it here.