Wikis: the New Blogs?

It's interesting how more companies are hoping that wikis are the new blogs. Mr Wikipedia himself was an early player here, with his Wikia. Now here comes Wetpaint (where do they get these names?). TechCrunch reckons that:

The service is incredibly easy to use (Jotspot comes close, but isn’t as mass-user friendly) - and it may bring a much larger audience to wikis than are currently comfortable using them.

I can see why blogs have taken off: it's vanity writing - a chance for the world to enjoy your wit and wisdom. But wikis are almost anti-vanity, since you let people scribble all over your precious masterpiece. Can't see it being so big, myself.