I am not sure if people here acknowledge stealing/pirating movies/music as an acceptable act. What we want is for the movies that we genuinely purchase (be it as a DVD or a direct download), to be more accessible and available on different platforms. Or we want services that make these resources free and yet make a profit to the creators (youtube/pandora). I believe that something I have already paid for should not be constrained to a device/platform and so will find ways to make it more shareable between devices/platform. I differ with the draconian laws used by the movie industry.

The thin line that separates the two things you are trying to compare is: In the case of movie/video sharing we are a customer (hopefully) of a service that is sold (music/movie) whereas in the case of copying a website, neither is the website selling their design nor is it in public domain for use.

I think it is ok to be inspired and create a "similar" design, but to plagiarize, is probably as pathtetic as it can get.