Artists want to be paid. the main thing is payment if the video is not a parody then there should not be any problem because there's need to get approval for making a parody. However, if for example the music used belongs to an artist then permission is needed for it to be used and getting permission is costly because it entails paying said artist. So, when the fair use act came to be it meant that it is possible to use this content without permission if the person using it stays the within limits.
What youtube is doing currently is e-mailing youtubers when they see that a video has copyrighted content. Not to mention if the content is a song they add a link to the original artist's youtube page/channel if they have one. They also write down the name of the song/musical content with links to buy them on amazone and iTunes. This is a good step since it helps the artists to sell their music to more people. Unfortunately this doesn't stop said artist from taking action against the youtuber that included that music in his/her video.
Artist might remove the audio from the clip everything even the parts that don't include their music or even have they video taken down.
My thoughts are how do we as youtubers come to term with artists since we are fans and consumers of their music. We use their music because there's a connection we feel to their music and at time we want people to know about their new song and albums. and sometime their music fits in pretty well with the video content that we create and at times it even emphasizes the massage that our videos have. We certainly don't mean any harm to our favorite artists.