There is something to make your own games/apps, it's called 'Indie Games', you can make anything from a Remote Controller Plane game to a 360 Controller Massage App...

Don't see why this accessory (Natal) would be any different or difficult to make apps/games for with 'Indie Games'

I'm getting it so I can browse my dashboard, movie library, Netflix library, send and receive party chat invites (I'm assuming this will be possible), play, fast forward, rewind movies, all without having to set my beer down or touch the controller! That alone is worth the price for me - games will be icing on the cake.

I think its a pretty good idea to give Xbox Live its own application store to seperate them from the games. Im really curious what the development community can come up with for the Xbox 360 and it would be foolish IMO for Microsoft to not throw it open. Heck they can even start the ball rolling by say offering a browser for $30.

Imagine a app store that included a decent media player for the 360, for example what if there was Xbox Media Centre available in app form to buy with significantly better codec support. The standard 360 inbuilt DVD player is pretty shocking so that could be improved too. Facebook has already shown what could be achieved with app integration if it was opened up to others.