I read this article and here is my quick response:

Google has more users than FB & TW, and FB & TW are mad….when a user is logged into Google, with a Google account, and is interacting with G+, then it makes perfect sense for the search results to change based on personal analytics. I believe Google will outperform in the long run.

Heres the difference IMHO: People use FB to search for things of interest so that they can connect socially with it or them. People use Google to search for everything, period. Why not tailor the results based on my personal preferences and/or the approval/authority rating of the people I’ve associated my self with on G+? It just makes sense.

ps…I Google Plused my Facebook page

pss….I think its funny that FB & TW used Google’s ‘motto’ ….clever