How to Upload Videos from iPhone to Twitter? Use TwitVid!
Simply record videos and share it with your friends with a few clicks. All videos are uploaded to TwitVid.com, user can use the Twitter login info to login to the site to manage or share their uploaded videos with others.
Here is one of the videos I shot to test the application.
Following screenshot should give you an idea of what the application looks like on the iPhone and how easy it is to upload videos from iPhone to Twitter!