If you've not been online for the last few days I'd advise getting the update to kinect sports.
It adds quite a few new games to the mini-games section as well as putting your high scores on the icons so you don't need to load the game up to find out your best results.
overall, It's not a bad update for free and the new bowling game pinvaders is very good.
If they keep doing this and adding features to the game it looks like its going to be one of the best purchases for kinect users at the moment.