Created attachment 176378 [details]
a random conversation and the contact window, note the hard-to-read nicknames in the conversation.

Telepathy butterfly should add support to msg plus! tags, since msgplus is so common among MSN users. 

Supporting the colors would be nice, but removing the tags altogether would be a very nice feature too, since it would reduce clutter and keep the contact and chat windows simple. 

I've attached a screenshot, showing a chat and contact window, and as you can see, the abuse of these tags hurts the usability making difficult to read the nicknames, and also add clutter.

In case you consider adding full support of these tags, there's some work on it in pidgin plus plugin, I'm not a developer but I hope it's not too difficult to port to empathy. Here's the link to the plugin in git:
https://github.com/frasten/pidgin-plus
Emesene and aMsn have full support for those kind of tags too.