I didn't get that impression. Are you referring to the ".edu" address of the creators of the site? Do you mean people with a ".edu" address, and therefore at an American institution, give you a sense of their work being higher quality?
I think he's referring to the "[edu]" label on the browsing pages (like [0]) which indicates that the uploader has a .edu email address. I'm not too sure about other countries, but at least in Germany, not many academical institutions actually have those, just normal .de ones.
to clarify: torrents are marked "edu" if the user has a .edu address, this makes those torrents stand out. The majority of non us universities do not offer *.edu addresses to their staff and students.
Yes, you're right. Which then brings up the question about how to determine if the data comes from an "academic" address, as was pointed out, only US institutions or institutions which are accredited by the US Dept. of Education can apply for an .edu top level domain— meaning nobody has it.