The good thing about music copyright violations on YouTube...
I've been using YouTube since 2006 back when it was still brand new (original start date was February 2005, for those interested) back when there were no partner programs and Google didn't own it yet.
At that early time, it was basically open season. The only things outright not allowed on YouTube at that time was porn and anything "grotesque", like decapitations and things of that sort like you'd see in a horror movie. Other than those two things, it's like I said, it was open season. You could post anything you wanted, and of course this included a crapload of guitar players posting somewhat-cover songs. I say somewhat because it wasn't really a cover but rather "guy playing along with a copyrighted song in the background".
I don't remember the year when YouTube laid down the ban hammer on "non-licensed use" of copyrighted music, but when they did, there were tens if not hundreds of thousands if not millions of guitar player YouTube videos that got pulled off the site is just a few short months. It was an absolute massacre.
When that happened, oh yeah, it was bad. Did I get caught up in the middle of that? Yes, I did. I received two copyright violations that took several years to get removed (and eventually did). I survived the massacre, but just barely. However, there were other guitar players who had YouTube channels that were nothing but videos of somewhat-cover songs, and got slammed with 3 "strikes" instantly and had their accounts disabled before they could even say, "WHAT THE F..."
So here we are now in late 2013. Google/YouTube has let up a little - but just a little - on enforcing copyright violations for guys who post somewhat-cover songs on the site. I have seen several somewhat-cover videos that obviously contain copyrighted audio used without permission, yet Google/YouTube lets it stay out there. As for why, I couldn't tell you exactly, but a video with illegal use of copyrighted audio in a video seems to be totally A-OK if it has stupid cats in it (as if there aren't enough of those).
Protip: The likelihood of your video using copyrighted audio illegally seems to magically stay up on YouTube if you put your fleabag cat in it. As for how long the "cat factor" will keep your video up, that I don't know. But it seems to work. And why don't I do it? My landlord doesn't allow pets. Maybe if I just used a thumbnail image of a cat it would work. Hmm..
This is the only cat video I like on YouTube. All others fail in comparison.
What was the good thing about all those guitar videos and channels that got whacked for copyright violation?
Yes, there as a positive to this. And the positive is that it eliminated a whole lot of crappy guitar covers off of YouTube.
Before the copyright massacre, there were two major problems with guitar videos. First, way too many cover songs. And second, way too many players who were playing the exact same thing. Badly.
If you want an example of what happens when everyone plays the same thing, just search YouTube for "super mario guitar". After watching a few of those you will hate the Super Mario Bros. theme song.
Even worse: If you click the "Filter" button on that search and choose "This month", there is always someone posting yet another cover of Super Mario Bros. played on guitar. It never ends. Kind of the same way Super Mario has a never-ending stream of crappy products on Amazon. The horror.
What I'm saying is that yes, I am glad so many crappy guitar covers got yanked from YouTube, because the vast majority of them just plain sucked.