you can quickly sort your tasks by due date in any project by using the "s" key on your keyboard. You can also view tasks sorted by date across all projects from the "today" view.
Unfortunately, it's not possible to automatically sort any new task you add, but we will consider adding such feature in future development. You're welcome to add a request to our Votebox: http://todoist.com/Vote/
Very helpful! Thanks so much for the quick reply!