The most recent spike is due to Baidu starting to accept Bitcoin and people speculating (not unreasonably) that nothing in China happens without the government's approval. Combine this with the fact that the Chinese are getting sick of receiving worthless American paper for their labour, which just gets devalued when they have accumulated enough of it. People are thinking China will switch to XBT and as a result it will become the new international currency (because, let's face it, whatever China says, the rest of the world must follow - if they decided to stop supplying us, we're dead - we don't have factories anymore, everything tangible that we had is now over there).
About the lack of regulation and verifiable identities - that's the allure of it :) It's not just the lack of inflation, it's the whole "Wild Wild West" atmosphere :) Like, remember the Internet before the old people and politicians found out about it?