The point is that they have POPs everywhere. Trying to find another ISP with that kind of coverage would be difficult. Otherwise, you'd have to either call long-distance, which would be quite pricy from Kathmandu, or set up a new ISP account everywhere you visited.

And the Java client is still there at http://toc.oscar.aol.com/, and it does something neat when you go to it. If you've viewing a web page and type in the URL, it goes to the new page, opens a new window with the AIM client, then goes back to the page you were originally on, so you don't have to bother opening a new window.