Of course!! There are some homebrew games and ports been developed now. I am working in one indeed
Also, I am very excited by the fact that kind people are nowadays porting OpenGL for Xbox. If OpenGL is finally released, lots of 3D ports and games will be possible. In my opinion, this is one of the most important works been developed at this moment.
Also, the recent release of IrrlichtX (by Freakdave) makes possible to port or program new 3d games easily. But IrrlichtX was released a few time ago, so there has not been nothing released with IrrlichtX yet (you know, developing or porting a 3D game is a long work).
The Xbox is still very alive, and I hope that we will be here for many years