Facebook may be the biggest social network in the world, but rival Google+ wins when it comes to user satisfaction.

Facebook users have become increasingly unsatisfied, according to a report from the American Customer Satisfaction Index (ACSI), which worked on the survey in conjunction with ForeSee, a customer experience analytics firm. Actually, Facebook's user satisfaction dropped 8% over the last year to record a 61 on a 100-point scale.

The report also noted that Facebook is not just the lowest-scoring social network, it also set a new record-low score for the social media category.

And as Facebook struggles with customer satisfaction, one-year-old rival Google+ made its first appearance in the survey, scoring a 78 out of 100.

"Facebook and Google+ are competing on two critical fronts: customer experience and market penetration," Larry Freed, president and CEO of ForeSee, said in a written statement. "Google+ handily wins the former, and Facebook handily wins the latter, for now."

The question, he added, is how much customer satisfaction matters for Facebook, since it so heavily dominates the social networking world with 800 million users worldwide. "But I expect Google to leverage its multiple properties and mobile capabilities to attract users at a rapid pace," said Freed. "If Facebook doesn't feel the pressure to improve customer satisfaction now, that may soon change."

Ezra Gottheil, an analyst with Technology Business Research, said he's not surprised that Google+, after being around just one year, earned better customer satisfaction ratings than Facebook.

"I would say that Google+ users are much more self-selected," he added. "For most people, Facebook is kind of a requirement, whether you like its style or not. You stay with Google+ because you like its style."

Basically, people use Google+ because they like its features, while some use Facebook simply because they see it as the best way to connect with friends and family. "I think some are outgrowing [Facebook], others are getting over their early infatuation, some are growing bored, and an increasing percentage are members out of necessity, because other people expect it, or they need it for some special offer or discount," said Gottheil. "

According to the report, the entire social media category slipped 1.4% to 69 this past year.

The category also has expanded over the past year.

Google+ isn't the only social network being rated for the first time this year. According to the report, the same goes for Pinterest, which scored a 69, LinkedIn, which had a 63, and Twitter, which garnered a 64. ACSI noted that LinkedIn and Twitter are considered low scorers.

Wikipedia tied Google+ at 78 to lead the category for a third straight year. Google-owned YouTube slipped a point to score 73.

Sharon Gaudin covers the Internet and Web 2.0, emerging technologies, and desktop and laptop chips for Computerworld. Follow Sharon on Twitter at @sgaudin, on Google+ or subscribe to Sharon's RSS feed . Her email address is sgaudin@computerworld.com.

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