All the good stuff by M$ has been ripped off open source, some of it unabashedly. For starters, take a look at SVG and XUL and then read about XAML. Look at the history of Mozilla and Firefox , then see how IE followed suit.
But when it comes to the UX - somehow nothing looks good. The real mud puddle is the Gimp program.
So instead of just ranting, let's do something about it. Let's define the open source interface.