Inherent in any hosted service, which includes most social networks. In a 1:1 comparison to Facebook, that doesn't seem like a relevant issue, though to the extent it matters I think Google has a better reputation than Facebook there. Many people already see Facebook as the company that makes privacy difficult.
I know this is silly but my view is: Fool me twice, shame on me. Facebook was first and I was fooled. I will not be taken in by Google+ or any other similar service.
There is simply no comparison in the manner Google treats your personal data with Facebook's attitude toward it.
At Google, as a dev, gaining access to personally identifiable information (that was hashed, anonymized like crazy, and scrubbed in every possible way to make damn sure there's no way the dev using the data could possibly track down any of the users) required jumping through so many hoops and getting so many different approvals and reviews it felt almost paranoid.
At Facebook, for years, they had a master password that could access all information on anyone's profile. They would just flat-out give this password to every single new hire, even people who weren't working with the data directly.
