I didn’t know that a last.fm founder is also on the Mendeley board, but now I hope for the best. It was also not entirely clear and obvious that I can add additional files and links but I’ll add them now. :)

Metadata correction/hashing: There’s a hashing that goes on behind the scenes already, but sometimes it fails when an item is present in multiple forms (like a native PDF vs. a scanned PDF) so it doesn’t always work. You may already know this, but one of the founders of last.fm is also on the Mendeley board, so expect this problem to get sorted out soon.

Adding supplementary data: You can do this now. The file box at the bottom of the Document details tab on the right allows you to add .doc, .html, .xls, .tex and many other file types. There’s also a space to add links.

Next to the DOI box is a button, that will do a look-up whenever you request.

On the website, there’s a related items feature on a article’s details page. It’s still under development, so it’s not perfect yet, but it’s improving quickly. Same for the stats.

Thanks again for the detailed review. I’ll be sure that someone from support follows up on this.