Google had earlier said that by unifying the policies, they will be able to use and share data from one service for the other. Basically, every user will be treated as a single entity across all the products offered by Google. The information that you give to Google+ can be used in personalized search results.
A lot of legislators, advocates, and the Federal Trade Commission believe that Google is trying to provide its customers a better service by consolidating the policies. But not everyone has taken as kindly to the changes. Many of the users have also asked about the data which the company will track and how will this data be used and protected by Google. They also feel that a customer should be able to opt out of any data gathering phase.
Google’s response will come on 16th February, but it has said that users can easily opt out of data gathering through various methods, like not signing in when searching. Even if you are signed in you can use the incognito window in Chrome. Or you could switch off the search history and change Gmail chat to off the record.