I feel WPF does have a lot of poorly conceived aspects to it, and there are many applications where it's use is completely unsuitable where that really shouldn't be the case. I'll admit I don't know enough about other UI frameworks to compare it to them well, but there's certainly a lot of times where I've found it brilliantly suitable for certain kinds of applications.

WLM2011 isn't a WPF application.

I would beg to differ. it doesn't show up on snoop, but I would be absolutely stunned to find the vast majority of the UI was not driven by wpf. If you have any source regarding it not being wpf driven I'd genuinely love to see it.

horrendously anti-aliased

This problem was fixed with wpf 4. Though the font rendering mostly looked bad because it jarred with font rendering in the rest of windows. Text rendered with GDI is not sub pixel positioned, in contrast to mac osx and linux. Whether this is a good or bad thing is a matter of taste. Many people prefer not to use anti-aliasing of any sort. IE9 will be using sub-pixel positioning and I'm willing to bet all text rendering will all be sub-pixel positioned going forward.