Google+ could probably deliver most of what Google needs from it without the Google+ site itself becoming a destination where hundreds of millions of people spend huge amounts of time on a daily basis. That’s the “social layer” approach Vic Gundotra and others describe, and that’s a valid strategy, especially with +1’s and search integration. That said, Google is still trying to make Google+ into a head-to-head competitor with Facebook and Twitter, via efforts like Hangouts, Circles and photo-sharing. In that context, the comScore numbers are pretty damning. Google makes a case for going slow on advertising and on APIs for third-party developers. But at the same time, Google is trying to support social games and company pages, both of which probably need more than viral promotion to become vibrant. That is, they need advertising, or perhaps some kind of a system like paid search, where companies can promote relevant content to users.