The song still sounds like a corny 80's pop song. IMO for the music to work it has to sound more otherworldly, or at least foreign.

I thought that the new ending music in ROTJ Special Edition was a huge improvement, BTW. Yub Nub was just downright ridiculous as was a very poor song to end the saga with IMO. If you listen to the album version it's even worse, because you hear just how ridiculous the vocals sound when there aren't party sounds drowning them out. That was one of the few instances of George Lucas noticing something he put in the movies was stupid, and decided to remove it.

As for Jabba's Palace though, as RoccondilRinon said they just replaced one dumb dated sounding pop song for another, except now we had obnoxious CG muppets singing directly into the camera as if it were one great big troll on the audience. Lucas could have fixed the scene by making it less annoying, but instead he just made it more obnoxious than the original. :(