[quote name='toper']TCR's?[/QUOTE]
In a nutshell, TCR's are the rules Microsoft has about each and every thing you do when making a game, and how you have to do it. More specifically it's about things you CAN'T do when making a game.
For example, one TCR is that pressing A must always select in a menu, while pressing B must always go back in a menu. If you made your game with the Y button selecting things in a menu, Microsoft would send it back after submission and make you fix it.
Another TCR is that in every live game, and xbla game, there always needs to be a way for you to select and view another players gamertag while in the game.
Especially with Live, there are tons of very obscure TCR's that are a pain in the ass for developers to implement just right to make MS happy.