I'm a bit of an audiophile, and in the world of headphones, Beats, Bose, and the big brand names are generally as a whole considered a joke. The quality of the big brnad cans that you pay $300 for is comparable to that of a <$75 pair from a more specialized brand such as Grado, Audio-Technica, or even Sennheisers. You really do pay for the brand name, and not much else.
That's why I'm skeptical of Beats on the 8X, while it may be a nice addition and could improve the quality compared to other devices, I'm honestly setting my expectations pretty low. I'm not sure if it even has a dedicated audio card, I'm pretty sure that MS' guidelines for WPs prohibit things like that anyways. Besides, if you REALLY want to improve the audio quality of your music, get better headphones, they account for much more than the audio player. I use the ATH M50s, and they're nothing short of excellent for the price that you pay.