Google Analytics Data Skewed Because Of Instant Previews
It appears that in some cases Google will conduct an on-demand fetch of your page to dynamically create an Instant Preview. The on-demand fetch happens when a searcher places his mouse over the search result on Google and the image preview comes up. Some analytics tools, including Google Analytics, may consider that a visit, because Google Instant Preview is actually visiting the page in real-time to get that on-demand Instant Preview.
There is no estimated time for when this may be resolved. So if you have seen a skew in your analytics data in the past two weeks, this may be the reason.
Postscript: The Google Analytics blog posted an update saying they fixed the issue at about 6:30 pm (EST). Note, they will not be reprocessing the data, so if you want to clean up your data, you can learn how to do so over here.
(Some images used under license from Shutterstock.com.)
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