IM at the library -from bad to good

The bad:
Instant Messaging has really improved since I started working at the library in 1999. At that time, the standard IM products such as MSN Messenger or Yahoo Messenger or AIM (AOL) required software downloads. MSN messenger seemed to be the popular choice and it would "sit" in the system tray waiting for a user. Unfortunately for the public environment, the default setting was "log in when Windows was started" and patrons would also tend to tell the computer to remember them so it didn't really log out or they would simply leave and not log out. The next person would sit down and, to their surprise, a little message window would pop up and the first person's friend would try to start a conversation, thinking their friend was still there. The worst case we encountered was when the online friend would start writing obscenities if the second person attempted to write something in the message window. NOT GOOD! And of course, people didn't want to leave when their time was up because they were in the middle of an "important" conversation. The decision was made to get rid of messenger because of the problems.
Getting Better:
Meebo made the situation better because computer users could go to Meebo, log into the IM accounts and when they closed the Internet, the conversations would go away. No problems for the non-IM-savvy patrons who didn't want messages to keep popping up, and we didn't have to play with settings.
Even Better: We have a shortcut on the desktop labeled Meebo IM to direct our patrons directly to that website.
My Preference: I like Yahoo because I can be in my Inbox page and see which of my contacts are online and click on their name without downloading any software. Gmail works the same.