I used the fancy new installer to install Eclipse Mars on my OS X box and since it was asking for a folder and had a lot of fiddly config details to set, I wasn't sure what it was going to do to my system so I created a new folder ~/Applications/Eclipse/ to put it in.
Fortunately it created an app package, Eclipse.app, so I wanted to move it into /Applications (out of my account folder into the common apps for all users of the box). So I dragged it (it's what you're supposed to be able to do, y'know).
DOH! That did not work. It crashes and crashes and crashes. Moving it back makes it happy again.
What would I need to do to move Eclipse.app, other than delete and reinstall and then reinstall all the plugins and SDKs I added?
Looks like the installer puts a lot of files, including the actual plugins, into folders under the .p2 folder in your home directory. This is true no matter where you install eclipse, with the installer. So either other users would need at least read access to some locations in your account, or you moved your .p2 folder to a central location and changed the eclipse.ini file (embedded in a folder under the eclipse.app folder) to point to the correct location. If you leave the .p2 folder in your account, you'd still need to alter the myeclipse.ini file, as it uses relative paths to files.
For your situation, you might be better off using the standard installation method (unzipping the distribution file), moving the installation to /Applications.