I don't necessarily think HTML and CSS make for good languages to design UIs with, but it beats the hell out of learning a new language, stack, and tools. I can

I don't necessarily think HTML and CSS make for good languages to design UIs with, but it beats the hell out of learning a new language, stack, and tools. I can use mostly the same tools and workflow to create apps as I would for making sites. That's one reason I can't wait for Windows 8. The promise of HTML5 apps, even if they're using IE as the runtime, is friggin sweet.