Our API directory now includes 88 project management APIs. The newest is the Trajectory API. The most popular, in terms of mashups, is the Basecamp API. We list 14 Basecamp mashups. Below you'll find some more stats from the directory, including the entire list of project management APIs.
Chaos usually reigns within most application development organizations; a situation that in many ways has been made all that much worse by the simultaneous rise of agile development methodologies and mobile computing.