I found AwareIM to be very easy to use. I have not written a single bit of html, java or any other code and have a multi-user web application running for my business. Its been up and running since AwareIM version 1.1. I have upgraded AwareIM several times and am now running 2.2. I have had 0 issues during upgrades. Also, my application has been revised 400+ times to add new functionality.
I like to relate the development experience to using MS Excel or MS Access. However, when you are done then everyone can use the system.
I'm sure someone with programming skill could write some very cool extensions.