I watched the ads, and I must say - I was not offended by them. There are definitely some caricatures I would rather avoid - especially snake charmers and cobras. But maybe I am not offended as many others are, because:
1. I have known Indians who talk like the two characters, though without the cow and snake charmer references. Perhaps that's because I am a first-generation immigrant to the US - FOB! Second- or third-generation Indian-Americans are less likely to find these heavily-accented caricatures even remotely familiar. (I speak English with a distinct accent, though not as pronounced.)
2. Many of the aforementioned Indians-with-a-thick-accent were also very smart - and the two characters in the MetroPCS ads are shown offering useful ("smart") advice to the poor, frustrated cellphone user. This is a "good" stereotype, is there is ever such a thing.
There are other ads that caricature Indians as lazy and incompetent (a la "Sambo") - in particular, a Discover Card ad featuring a guy (who looks White!) with an Indian accent and calling himself "Peggy." These ads definitely make me uncomfortable, and I will probably give Discover a call over this, if not cancel my account altogether.
But the MetroPCS ads? Naah, not worth wasting my time over.