Current events-"copyright infringement"

Is the whole PIPA/SOPA copyright infringement pretext for censorship? It's the same "reason" why some youtube videos are being taken down.

http://www.youtube.com/playlist?list=PLE6FD224009596635
http://www.youtube.com/playlist?list=PLB03811B9F6B70AFB
http://www.youtube.com/playlist?list=PLDFC6A8D158C738BF