I've been using and upgrading Ubuntu since the version 9. Of course, I have 13.04 now and after installing a clean 13.04 to another computer, I've noticed quite a few differences (plymouth, lightdm, some software behaves differently, etc.). I've done quite a few customizations during the period so it's probably due to that.

So I wonder if there is a way to see what's different between my and the clean version. Not the complete file list diff, but perhaps software package differences (synaptic?) or something that will be easier to read and compare. Is there a way?