People vastly underestimate how important this effort is within Google. This is not something they are going to work hard on and then leave fallow like Google Health, or give up on after a few months like Buzz. They are going to grind on this with everything they've got like they are grinding on core search. The Plus team will become one of the most selective and elite teams within Google, on par with core search. Just as every Google product is designed to be search indexed, so too will every product now (and going forward) be designed to have sharing/collab built in as core. [1]

People forget that new features do attract new users. Facebook is Facebook because it didn't stop at profiles, it added News Feed, Platform, Chat, etcetera. Reports of Plus' demise are thus much exaggerated.

Anyone who has ever launched a product knows that there is a trough after that first media driven euphoria. That trough of despair shouldn't get too deep or take too long to exit, but there is no business that hasn't had one of those after a successful press driven launch.

At a minimum, even if they are only the strong #2 to FB as a consumer social network, they will own "Facebook for business" when they launch Apps integration. It is the most obvious way to instantly bootstrap a fully featured collaborative company social network within the organization that works with rather than supplants email. This is quite hard to do right without being the email provider as well, rather than a third party service like Yammer or Asana[2], but Plus does it well: email under picture for quick private messages, Plus for more public and publicly searchable posts.

[1] To its credit, Microsoft also gets this now in that all apps in Metro are search providers, dashboard providers, social providers, and more generally API providers.

[2] I feel bad for both of those companies. As excellent and well executed as they are, can't see how they can compete with Plus for Business.