differ between email and im notification

Another issue I experienced when testing Ubuntu's empathy package (cf bug #658328) is that the indicator applet doesn't make any UI difference when you receive a message or, say, a call. Messages are "semi real time", you can wait a bit before replying, but the initiator of an audio/video call expect you to reply ASAP. Such events should be displayed in a more "aggresive" way.
This is probably true for incoming file transfers as well.

What happened to IDO (Indicator display objects)? I think this would be the best use-case for them. I have been experimenting with them once, and also found a video on twitvid: http://www.twitvid.com/GNUXF. What do you think?

i agree with #1. I allready missed file transfers in this way.

The title of the messaging menu has two primary objectives. First, to let you know at a glance whether you have new messages, so you can choose whether to read them. And second, to let you know at a glance what your current chat status is, so you can tell whether you need to change it.

Currently, it's failing even at the second of these objectives. So adding a third objective -- distinguishing between mail and IM notifications -- seems infeasible. To meet that objective, we would need to double the number of icon variations: from "you have messages" + "you don't" to "you have e-mail messages" + "you have IM messages" + "you have both" + "you have neither".

"the applet shows the login of a pidgin buddy with the same symbol as a new email." A buddy signing in isn't a new message. So I suggest that by default, a chat client shouldn't highlight the menu title (shouldn't "draw-attention") just for someone signing in, even if it's shown in the messaging menu.

"the indicator applet doesn't make any UI difference when you receive a message or, say, a call ... the initiator of an audio/video call expect you to reply ASAP. Such events should be displayed in a more 'aggresive' way.
This is probably true for incoming file transfers as well." Yes, the messaging menu is not for incoming calls, and I've sketched how incoming file transfers might be shown in a classy IM program. <https://wiki.ubuntu.com/NotificationDesignGuidelines#Morphing_window>