depends on what mainstream you're talking about. UK has a ton of south-asian influenced music regularly on the charts. In the US, there have been plenty of stuff from Timbaland&Magoo, Afrikaa Bambataa to "Addictive", there have been songs on top of the charts. Yes, Mundian is the biggest, and certainly the most recognizable. But come on man, where was the second song? It didn't come because Mundians popularity is like Tunak from Daler Mehndi. It's a gag song that people laugh to and try to 'screw the lightbulb' and 'turn the doorknob'.
I try not to hate on it because it did expose the US mainstream, but I'd rather it die and a solid artist like the1shanti or Makaveli or Kidd Skilly make some headway.
gah, sorry for the post. I know this was supposed to be a funny and light-hearted thread. So as an apology I give you this (this may have been posted, not sure I haven't been keeping up)
[flash=200,200]http://www.youtube.com/watch?v=9DFCUAjH0G8[/flash]