The phrase "sell out" is always used in a derogatory way. Let's step back a bit and analyze why Metallica "sold out".
The core of this band, Hetfield, Ulrich, And Hammett have been making recording, and selling music their life since they were 15-16 yrs old. At what point do you think they said, "Hey we don't really have any other skills, so lets listen to what the record company says and see what happens.
Don't get me wrong, I was a die hard Metallica fan up to And Justice and I was crushed when they warned us that they were going in a new direction and then released the Black album at which point I felt violated and exploited. How could they do this to us? I spent so much time, money and loyalty on them for them to go chicken$hit on me?
But I digress.. I stopped listening to them altogether and hated them for years. Around the time I turned 28 or so My IT career started taking off (stay with me here a moment) I had 2 children (now 3) to take care of and thought there would alwys be a need for a PC Technician that could troubleshoot just about any PC issue. Then came outsourcing, the company I worked for laid me off after years of loyalty because they could save a few k a year.
In short, since then I've been a PC tech contractor,a cook, a janitor, a pizza delivery guy,and a security guard. I got back into a company making decent money doing what I do best and they also laid me off after a couple of years.
My point is that it's scary out there when you have few skills and when faced with extinction you may do things that you normally wouldn't do to stay alive. I think Metallica "sold out" because they knew they could be nothing else but musicians. By the way I still can't stand their new music but I understand why thy did what they did.
Sorry if I ranted but I wanted to shed some light on some of the folks that may think that "selling out" is always a bad thing. Sometimes compromising your integrity whether it's musical or not is what you have to do to be succesful, or just survive in music and in life. Take it from a lifelong Punker..
We see things as we are, not as they are. - Anais Nin