Go to the game list you want on Xbox.com. At the end of the URL type "&compareto=YOUR GAMERTAG" but without the quotations, and replace YOUR GAMERTAG with your own tag. From then on, just copy the whole URL, but delete everything but that line each time you change list.
Ah, good. Yeah, it annoys me because people always use it when they want to pretend they didn't mean anything by what they said, and want me to look like the bad one.