Yeah, that's what I feel gives markdown an edge over nearly anything else; markdown is adopting conventions that were meant to be readable without any kind of rendering. I can very easily tell what my markdown document is going to look like before I render it with Pandoc, because it's basically just taking stuff people were using with plain text that was meant to be read directly anyway.

I haven't used rST, but looking at the examples it looks considerably less readable out of the box.