Guild roster listing if not actually playing
Blitz | Rogues to Riches [RtR]
You know, I had something similar. I was playing in Guild Wars doing some skill capping and trying to get my Hall points up and my guild leader in Guild Wars 2 saw me as online. So he was trying to talk to me. Of course I wasn’t responding as I saw absolutely nothing in chat where I was so he phoned me to make sure I wasn’t hacked.
In the end we worked out that if your accounts are linked, it thinks you are online in GW2 if you are in GW. But with no cross game chat, no-one knew what was going on.
I definitely like your idea. It would be very helpful to a lot of people.