According to (ACSI) Consumers not satisfied with Facebook

The American Customer Satisfaction Index (ACSI) released on July 19 a report on consumer satisfaction with the internet, including social media. The report found that Facebook was the lowest ranked site of its kind. 
The 2011 American Customer Satisfaction Index E-Business report, the 12th of its kind, was produced in collaboration with analytics firm ForeSee Results. The report uses data from over 70,000 customers and measures satisfaction on a scale on 1-100.
This year in the category Internet Social Media the report scored three websites -- Wikipedia, Facebook, and YouTube (Google) -- plus "All Others"; MySpace was not included in this year's report.

Of the sites measured, Wikipedia scored highest with 78, YouTube (Google) came in second place with 74, followed by social media websites under the category of All Others with a score of 67; social networking giant Facebook, meanwhile, came last with a score of 66.  
An outline of the report is available on the website of the ACSI.
Whether customer dissatisfaction with Facebook will lead customers to switch to Google's new social network Google+ remains to be seen; however, it does appear that customers are moving away from Facebook. This trend away from Facebook was indicated in a separate report released June 12 by Facebook monitoring site Inside Facebook, which found the amount of active monthly users on the social networking site to be declining throughout the North America and parts of Northern Europe.