I just tested the eclipse callisto release. The purpose of this project is to get the 10 main eclipse projects together in one simultaneous release. This should increase the usability and facilitate the working with this different projects in just one eclipse distribution.
It is as easy as using the callisto update site with the eclipse update manager. The new remote update site for callisto is:
http://download.eclipse.org/callisto/releases/
After connecting to this server, you can install the features you need. If the selected feature requires another feature, the required project can be added using the 'Select Required'-Button.
I can say more in a little while (testing while working with it). All in all the first impression is really good. Right know I have different eclipse distributions installed on one system. One for each top level project. Hopefully we dont need that anymore in the future…