It's not PDFs that are bad so much as Acrobat. When I'm using kghostview or something else that doesn't require me to go work on another task while I'm waiting for it to load, I don't mind clicking on PDF links. Of course, a lot of people abuse PDF and use it where they should just be using HTML, but that's not the technology's fault.

Seems like a cool concept though. It could have some better widespread use when they make it 'myspace compatible'.