I added Twitter to my iOS app. I\'m using iOS 5\'s TWTweetComposeViewController in ShareKit. It returns TWTweetComposeViewControllerResultDone. So ShareKit gets to sendDidFi
Don't know if this is related, but in simply trying to send a tweet today via Safari on the iphone I got the "Cannot Send Tweet" message. Some experimentation revealed that the tweet was too long. The tweet contained a link, which Twitter automatically shortens and calculates for in the amount of characters left that it displays for your tweet.
Looks like Apple is calculating this incorrectly, because although my tweet showed 3 characters remaining in Safari's tweet bubble pop-up, when I pasted the same information into the iphone Tweeter app, it was over the limit. Once shortened it posted fine from Safari.
So I would say Elissa Tong is right - "Apple's Twitter framework is missing additional error checks and notification messages."