I wonder why also... Maybe to minimize production cost? I've only seen one issue with slot loading drives and it's with a wii, where their children decided to put anything disc like inside, such as coins. Don't think it'd be too much of an issue with the 360 with its demographics...
Yeah but the demographics for kinect are going to be children, most of the games they demoed are going to appeal more to kids then adults.
hmm then more reason for no slot loading drive, kids will fill it in with random stuff.