So on my friends list I can see if my friends are in the middle of a current game, it would be sweet if I was able to PM (Private Message) them during their game and just let them know that I want to play with them next game or ask them how their game is going.

I was going to start a thread on this. It would be easier to pm a friend in game rather than having to alt tab to your buddy list. This addition to the game would be nice because of the reasons that messiahforhire stated