Has Google plus Already Peaked?

Average time on Google+ fell 10% in the last week, which might mean the service has peaked in usage, according to numbers from web analytics Experian Hitwise.
Google+ is racking in amazing signup numbers. 20 million users in one month! But that's relatively easy to accomplish for a service which is basically advertised on every page of the world's most visited site.

The real question for Google+ is whether people actually use it. Google+ is going after Facebook and Facebook is almost addictive: people check in several times every day to see what their friends are up to, look at photos and play games. Usage is ultimately what will determine whether Google+ wins or not.
Of course it's way too early to call Google+ dead. The numbers could be wrong (no knock on Hitwise--web measurement is as much an art as it is a science), or they could just be a temporary dip.
But it's important to remember that what matters for Google+ is usage as much as how many people sign up.
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