Hereafter Twitter will support only the oAuth API access.
The switch to OAuth is a good thing, because of below reasons.
* don't have to worry about exposing the credentials for your users whether through a bug or other means (especially considering that a lot of people use the same password for multiple services);
* don't have to worry about the user changing their password — a user can change his or her password and the OAuth "connection" to your app will still work;
* don't have to worry about other applications masquerading as your application - only you can set the byline with your application name;
* will eventually have access to more APIs from Twitter that will only be available to "trusted" OAuth-enabled applications; and
* give the @twitterapi team more visibility into the network.
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