Yeah discoverability is a little bit of an issue, I think we eventually want to move to a consistent “one shortcut for everything” which we’ve seen in some other apps. So rather than having @ # or / work for different things… we’d end up with one shortcut that can be used for users/categories/tags etc.
Google Docs is a good example… they use @ and you can search for all types of things:
This could work for us, because mentioning people is fairly intuitive and common… so once you’ve done that you can discover all the other available functionality.