I would really like this feature added too.
Specifically when I share a notebook with a guest, that they then see any assigned tags in their tags list. This doesn't happen currently (at least on the web version).
I use Evernote to manage my virtual assistants - and I want to be able to quickly create a note on the go, tag it for a certain assistant task and for it then to appear in the tags list of my 2nd Evernote account (which the virtual assistant checks).