EAP builds get bigger and bigger, I have to think twice before downloading another 40Mb update. Why not to release incremental binary patches along with full versions?
For example Xdelta can be used: http://xdelta.org/
I've used idea3177.tar.gz and idea3193.tar.gz, both about 38Mb, to test it (don't have intermediate builds so actual results should be better). Xdelta made a 15Mb patch in several seconds.