It looks like any third party twitter clients that survived tweetageddon will now have to embrace OAuth for their applications over the next 48 hours or face tweet extinction.
If you are like most Twitter users, you have used use a third-party Twitter application to read or send Tweets. As of August 31, Twitter applications will all use OAuth, an authentication method that lets you use apps without them storing your password. [...]
The move to OAuth will mean increased security and a better experience. Applications won’t store your username and password, and if you change your password, applications will continue to work.
With OAuth, you still individually approve each application before using it, and you can revoke access at any time. (Official Twitter Blog)
Many developers (especially those on the iPhone) have already embraced OAuth months ago, although there are a few who have yet to adopt the feature (although most of those apps are not actively supported).
Although OAuth does make configuring a few blog plugins a little frustrating (as many of them need extra TLC in order to connect to ones account), it should help Twitter reduce the number of hacks against twitter accounts in the future.
Other companies like Tumblr are also encouraging third party developers to adopt OAuth, a trend we might see gain popularity across social networks as well as blogging applications.