Hm... what about web-based RSS readers? Technically speaking, if you're running one, you are copying someone else's content and putting it on your site, even t

Hm... what about web-based RSS readers? Technically speaking, if you're running one, you are copying someone else's content and putting it on your site, even though the application belongs to a user and he picks what he wants to see up there. There was a startup mentioned here recently, that allowed you to track changes on various web pages, and view the difference (it obviously stored copies on them), how legit is that?