Omigoodness, I'm going to make a note here before accusations against each country gets thrown around. Please, do not make this into a thread about how Japan is superior to America/Westerners just because. I've seen it happen before randomly and it's very frustrating to see as an Asian-American. But you've all been great.

While opinions vary, it's just as close-minded to say that "Japanese music is better because it's always less sexual, better lyrically..." etc. BOTH American and Japanese music have drawn inspiration from other places but there's more to BOTH countries than just the mainstream popular music. I just want to point out that there is good and bad music coming from both ends of the world.

As to answer the question, "ripping off" is a very strong statement. Influenced, yes, but not blatant copying. Sometimes it's really obvious that certain Jpop songs borrowed the same tune from American songs. Though, none of my American friends have ever said, "OMG, Japanese music is just like ours!" LOL. There's a difference in vocal range and pacing IMO. Anyone notice that like all the male singers in Japan sing the same way? I can't describe it... On an interesting note, my father thinks that modern Japanese musicals are incredibly influenced by Broadway (think Sondheim, etc)