The service also noted that it is the Do Not Track (DNT) function found in a number of web browsers. Browsers supporting DNT include Firefox 5.0+, Microsoft Internet Explorer 9.0+, Apple Safari 5.1+, and Chrome 17.0+ with a third-party extension.

When DNT is activated, Twitter will your account based on the places you visit on the Web that have Twitter buttons on them. What's more, tailoring will be shut off by default if you have DNT activated when you join the service or if it was activated before the tailoring feature was launched. You can also shut off tailoring manually through your account settings.

Twitter clarifies its explanation of how it shares data. For instance, it will share data you give it permission to share, or when the data is not private or personal.

It will also share data to protect the safety of a person, to counter fraud and protect system security, and to comply with requests from law enforcement and regulators.

However, that doesn't mean the service will roll over for the law whenever it comes knocking at the door, as is being illustrated in a recent case involving a in New York City. In that case, Twitter is refusing to turn over to prosecutors the tweets of Malcom Harris, who was among a group of demonstrators arrested in October 2011 for marching on the roadway of the Brooklyn Bridge. Twitter has been ordered by a court to turn over the tweets, but it's appealing that decision.