The onscreen text shows when you are hearing the CD and the Guitar Hero (GH) versions. Take a listen & a look, and make up your own mind. The problem is especially bad at the end of the sample, where the video loops a few times. Which is better ?
(Note that YouTube changes the audio into mono by default. I have linked to the hi-res version, if your computer struggles to play this, click on the video to go to YouTube itself to see the "Normal" version. However the audio is much lower quality in the Normal version, making the differences harder to hear.)
If you think the distortion on the CD release sounds bad, please go and sign the petition, even if you're not a Metallica fan - this is our chance to send a message to the music industry that enough is enough, and we want decent-sounding records again !
Don't be fooled - in some ways, the CD version does sound better than the GH version - fuller, and warmer. I've written more about this here. The distortion ruins it for me, though. If the CD's mastering engineer, Ted Jensen had been given a clean version to work from in the first place, he could have made a master with just as full and warm a sound, even more harder-hitting, but without the distortion.
If you want to know more about why they sound so different, check out my post about the "Loudness Wars" here, or visit http://www.turnmeup.org/.
These clips sound like the same ones I was sent and used for my original comparison - whoever created the samples has been turned down the CD version, matching the levels so the differences can be heard clearly.