Google announced on Tuesday that Google Analytics will now not show you the keyword queries that users search for and find your web site, the keyword referral data, for users who are logged into Google during their search. Otherwise if the user is not logged into Google while searching, you will see the keywords used to find your web site.

From Google Analytics blog:

How will this change impact Google Analytics users?
When a signed in user visits your site from an organic Google search, all web analytics services, including Google Analytics, will continue to recognize the visit as Google “organic” search, but will no longer report the query terms that the user searched on to reach your site. Keep in mind that the change will affect only a minority of your traffic. You will continue to see aggregate query data with no change, including visits from users who aren’t signed in and visits from Google “cpc”.
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From Clickz.com:

In a move with unpleasant ramifications for marketers, Google will no longer share keyword queries used by its logged in users before they jump to a website. As a result, webmasters will no longer be able to find out that a visitor arrived through a search such as “Gucci” or “foot surgery.” Instead, they will know only that someone arrived through “organic search.”

This change came about as Google made SSL Search the default encryption protocol for users who are logged in. On the upside, marketers can still get keyword referral data for visitors who are not logged in or who enter their sites through paid ads. That’s a majority of Google search users.
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