I don't know about you, but if someone did this in my sacred space, I would be offended. I don't mean that Russia's powers that be (government and church in cahoots) should be able to imprison people for years over this sort of behavior. I think not. I personally relish hearing the words Pussy Riot in the news, and am glad that women there feel powerful enough to do this. Putin's continuing reign is a far greater blasphemy than the most raucous of punk rock in a cathedral.
In spite of my sympathies for their causes, I would be totally pissed if somebody made this kind of noise in my sacred place. Blast that crap at the river? Get OUT. I understand anger, and suppression, and the need to eliminate Putin. And I understand the outrage against their methods. Too bad the punishment is so out of proportion with the offense.
Here's the NPR story: http://www.theworld.org/2012/06/anti-putin-punk-rockers-pussy-riot-to-stay-in-jail-await-trial/