Check this site http://www.itwofs.com/, quite a interesting one. I was surprised that there is so much plagiarism in film music,i think Karthik ( site moderator) is doin a tremendous job.
It does question the Artist creativity and integrity and iam not justifying, but the flip side is everybody gets to enjoy the music, i mean how many in India would listen to music made outside Indian languages.
The urbane would mostly be hearing to English only and unless its a ditto,most wouldnt recognise. How many listen to different genre of music, but if the same is made in their native language in a film,it appeals the respective group,
and reach is more, otherwise we may never hear them anytime.
When i was listening to the songs, as a listener i felt some songs original was better, in some the copied/improvised version was better,end of the day the audience get to listen to different kind of music.
Had gone to Grand canyon in 2004,we went to watch the film in imax theatre, and when we stepped in we got so excited, guess what, we heard a tamil film music in American native song ( 'Ly-O-Lay Ale Loya'), this comes in the song Theeradha tham venum from the movie Parthiban kanavu, at that time we were wondering whether by any chance tamil song could have the source,i saw this song listed in the site and remembered our encounter.