I am not sure how useful it is, but this Twitter feed is certainly clever and shows some other possibilities. What would be more clever, more interesting, and potentially more useful is to Tweet information which is contained in an XBRL filing. Because it is easy to extract information from within an XBRL filing or across XBRL filings; the combination of XBRL and Twitter can be a great way to make all sorts of information available.
Imagine, oh let's say a produce broker (because I use to work for a produce broker and know a little how this works), using a mechanism such as this for making information available to suppliers on what he is interested in buying or customers keeping them informed as to what he has available to sell, special deals he has on produce he has to move before it spoils, etc.
Creating a dynamic information feed using Twitter or an RSS or ATOM feed or some other such mechanism becomes child's play. Or, taking someone else's XBRL feed, extending it, adding additional information (basically mashing up multiple sources of information) is another possibility.
One final idea. What about creating a botwhich monitors some piece of information, sending out Tweets which you can get on your iPhone. Maybe, using my produce broker example, it monitors the price of lettuce offered by several brokers helping you to get the best price or helping you identify when the price point where you want to start acting has been achieved.
The Semantic Web is going to be great!