As you type, Google Suggest communicates with Google and comes back with the suggestions we show. If you're signed in to your Google Account and have Web History enabled, suggestions are drawn from searches you've done, searches done by users all over the world, sites in our search index, and ads in our advertising network. If you're not signed in to your Google Account, no history-based suggestions are displayed. Data you send to Google is protected by Google's privacy policy.
More about Google Suggest
As you type, Google Suggest communicates with Google and comes back with the suggestions we show. If you're signed in to your Google Account and have Web History enabled, suggestions are drawn from searches you've done, searches done by users all over the world, sites in our search index, and ads in our advertising network. If you're not signed in to your Google Account, no history-based suggestions are displayed. Data you send to Google is protected by Google's privacy policy.
http://www.google.com/support/websearch/bin/answer.py?hl=en&answer=106230
in my case,i wasn't logged in...and my web history is turned off.so this is a global thing... :-D
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How glorious it is - and also how painful - to be an exception. - Alfred de Musset