I, too, expected this from Google. They are not creative enough to find new niches or products, so they just grab what's lying around and integrate it into their main real estate, the Google search engine.
Ultimately, this strategy will fail. If economic history teaches us one thing, it is that people WANT diversity; they WANT variety. They WANT to be able to chose between offerings. Translated to the web this means: they WANT different sites offering different products and services, different approaches to the same problem.
Or vice-versa: they don't want GOOGLE for everything. They will be turned off by the boring single provider that promises them everything. If you could get your favorite cereals every morning from now to the end of days, but just these, how long would it take you to be entirely fed up?
Unless Google is much much better than competing sites, they will only be able to grab a fraction of the money. Given the size of the market (and considering Google's strengths), this is still real money. But I don't think they will reach the same level of near monopoly as they did in search.
I stopped using Google 18 months ago and switched to Bing. While I still use Google occasionally, I don't like their approach to the web and see how they are hurting us webmasters in the long term.
Disclaimer: I am not affiliated with Microsoft or Bing, and I do not hold their stock.