People are reasonably getting rewarded for building something, but rather than making VC's rich, they are allowing themselves to be absorbed by larger companies (somewhat similar to Kodacell in Themepunks).
My favorite part comes in the comment by David Nemesis:
As far as I'm aware nobody who's hit it big because of Web 2.0 has quit their day job, but a number of their day jobs are now being acquired or subsidized by BigCos, and the end result will be a healthier, more innovative Web regardless of whether it's tagged or Google Mapped or built with agile development practices. That's pretty exciting.
This indicates that big companies are providing the infrastructure and support for interesting tools, rather than building up a new team to do the same thing as that tiny, new organization. Seems to me like everybody wins in this situation - at least for a time.