Definitely... the .pdf readers in OSX and Linux work much better.

The .pdf reader in Windows that feels the most like a *nix .pdf reader is Foxit PDF. The Foxit PDF editor is also pretty nice, it lets you edit .pdfs at a relatively low level of markup and spacing.

So maybe the popularity comes out of ignorance?

yes. but that's not necessarily a bad thing to say about scribd. if scribd makes it easier for people to not know anything about how to use computers, then that's valuable to lots of people.

Scribd should win some award for being the most counterintuitive successful startup. It's hard to imagine that computer science majors came up with this idea!

youtube doesn't do much besides make a few things easy: make a file web accessible and convert to another format and provide comments and some text people can paste to embed it, and i guess favorites and a bit more -- all the kinds of things scribd has i think. plus give away free storage space and bandwidth, which scribd does too.