So, what's Qwiki's technology that's so powerful here then? I think the sentiment is that their technology isn't anything special, and they don't have any other particularly distinguishing feature, so why such investment?

With Powerset, the value was supposed to be in the technology, even if the demo was on Wikipedia. With other companies, say, Twitter, the power is in the size of their network and potential for something, even if the technology isn't groundbreaking.