Everyone should have the IM icon near their names, but in your profile you can set it to either show or hide your email address, thus why some people don't have them showing.

Future mods will make the IM easier to use... I just coded a quick means to msg each other as I didn't have the time to create the complete tool I wanted, which will open in a small seperate window much like the common IM tools now. (AIM, MSN IM, ICQ, etc)

]=)