IE8 and IE9 are indeed much better. Unfortunately, IE6 still has a presence in much of locked-down Corporate America, and I get hits in my logs from both IE5 (!) and IE7.

As for ASP.NET, I hear about it, but I've never see it outside of a book or a blog post. I'm in Silicon Valley, so that certainly biases things. I know of people who use it (e.g., the Stack Overflow team are happy using a subset of ASP.NET), but it's always somewhere else. In my world, Nada. Ditto anything else running on IIS. I could reach out and touch boxes running IIS in 2002. Now they're completely gone. That's a huge shift.

Let's be accurate with Microsoft. IE 8 has some backwards compatibility shims that are evil. IE 6 is the required browser at the Fortune 20 company that employs me. There is no single aspect of the WWW that has poured more time and money down the drain than IE 6. I joke about bringing a class action suit over it but just barely.

jQuery was very popular before Microsoft started to ship it and their "endorsement" changed little if anything. It was the result of jQuery's utility, license, and footprint.

That said, and I truly dislike Microsoft for many reasons, IE 9 is shaping up to be the best browser there is and by quite a bit.