Thanks for the 'snip'
No there is no advatage, just ergonomics. In fact a lot of people have had issues with disc scractching or ring burning in the upright postion, whether or not the machine is moved while playing. This is not a Microsoft problem, Microsoft did not build the drive, Toshiba did so if you want to blame somebody.........
I think Microsoft has learned its' lesson on the 360 though and their next system is probably going to be as bulletproof as the original X-box whose only problem was bad power cords and a crappy Thomson DVD drive. Even those problems weren't as widespread as the 360's though.