They may still show when you're messaging someone and hit 'reply to', but they shouldn't be showing up in the Ningbar itself when you do things like check your friend requests. if you're seeing anything like that, please let us know.
i see them when i hit reply to in the ning bar, and i also see them on the share page (when i share blogs/photos/videos etc), when i select "share with friends".
Yes, the Ningbar isn't 'network aware' so it can't know what someone's profile name on a specific network is. We'll be migrating messaging into the network app and out of the Ningbar; until that happens this will continue to be a problem I'm afraid.