We currently have users experiencing issues with allArticleAnnounce and allInstantTweet no longer posting to Twitter and Facebook.
The major issue that has been discovered is Basic Authentication (Username & Password) has been deprecated. All applications/extensions that integrated externally to Twitter must now use OAuth. This is a considerably more secure way to authenticate externally.
You can find that Twitter was under maintenance over the past several days as well, which would explain many of the outages before the update http://status.twitter.com/
Whilst we take all measures humanly possible to make sure that our extensions integrate with the systems as advertised, the third party software/services they utilise are unfortunately out of our control at all times.
We are currently working towards releasing an update which will fix the above issues. This is already underway but will not be up until Monday at the earliest due to testing and writing the associated documentation.
Please keep an eye on our front page, Twitter and Facebook pages for the notification of the new update.