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Twitter has begun automatically shortening URLs pasted into tweets by its users, the microblogging site announced today.
When users compose a tweet and paste a link of any length into the Tweet box, Twitter will automatically abbreviate the link to 19 characters when users hit send. In testing for almost exactly a year, the service--called t.co--is being rolled out incrementally and will wrap and abbreviate all links shared on the site in the same way other URL-shortening services, such as Bitly, do.