I'm struggling to see what sort of application this new Wave thing will have. Mind you, it took me a long time to find out the point of Twitter, but now I think I know what that is all about.
To me it sounds like some form of informal/formal get-together package - real-time minute-taking and ideas processing, if you like, with friends profiles and chat thrown in for good measure, so yeah, a bit "IC-Flick-ipedi-Face" with a hint of cloud. Might prove useful in business and medical/research fields.
I'd need to try it out for myself and see how it works, before I'll know if this sort of thing will catch on. If only I had friends...