Nick Brisbourne’s right, but I think he makes the stereotypically America mistake of infinitely extrapolating a short-term trend. I’d get Asian on these projections and call this, “The cyclical nature of individual site ownership.”
Now that microblogging and feed synthesis is stablizing (oh Feedster, too early again, dammit!), the basis for competition will move to personalization and distribution — bringing these capabilities back to our own domains on our own terms without losing the benefits.
These fab Internet famous are going to bring the goodness home, and so will we.