I think it would be a great thing for mayors to have that once one of their towns members or friends log on there would be a message popped up in chat that would tell you that they are online, or a system that if you did (/region member online) it would tell you who from your town is currently online.
I would like this, but only for the friend thing. Have an actual friend list that would be like most social sites (friends require both people to agree) This is because certain staff members value their privacy (**cough cough AndrewandRevan cough cough**) and it can be abused by adding them to your town.
Take advantage of the clan/party system and make a group of freinds in your clan, so you can simply do /party if you want to see who's online, even if they are vanished. Cool eh?