There are confirmed reports that Google Instant Previews may be skewing your web analytics data.
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.
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