In Galileo and Helios Provisioning Platform were introduced, and non-update-site plugins now should be placed in "dropins" subfolder ("eclipse/dropins/plugin_name/features", "eclipse/dropins/plugin_name/plugins") instead of Eclipse's folder ("eclipse/features" and "eclipse/plugins").
Also for programming needs the best Eclipse is the latest Eclipse. It has too many bugs for now, and all the Eclipse team is now doing is fixing the bugs. There are very few interface enhancements since Europa. IMHO.