In order to communicate w/ someone via IM, you must have both their "Service" (Yahoo, AIM, etc) AND their Screen Name. Therefore, if IM Screen Name is included as a Profile field, the IM Service drop-down (selector) should be automatically inserted in Profile FORMS (Add and Edit modes) on the same line after the field label and before the Screen Name text field. If the IM Screen Name is required, then a Service Provider field value is also required.
In View mode, display the selected Service Provider after the label and before the Screen Name.
In Listings (selector) - include the Service Provider value after the screen name in parentheses: "dggreenberg (AIM)"
— Original Post from Elin W ---------------
Currently when IM screen name is selected the drop down of address types is offered. However, this is not appropriate for IM Screen name and also not useful since without the service name, you can't IM.
The way it should work is, select IM name, then get a dropdown with a list of service providers.