It's important for me to remember sometimes when I created a task in PlannerMode. Since uncompleted tasks (which in my life is, um, most of the them) get moved forward each day, I can quickly forget how long ago a particular task first landed in my lap. Also, it could be helpful to sort tasks based on their age. Putting a timestamp at the front of the task description when the task is created is one way to handle these issues. Here is the diff for what I changed in planner.el to do this:
< (let ((plan-page (or plan (planner-task-plan info))) < (date-page (or date (planner-task-date info))) < (live-buffers < (and (equal planner-tasks-file-behavior 'close) < (buffer-list)))) --- > (let* ((plan-page (or plan (planner-task-plan info))) > (date-page (or date (planner-task-date info))) > (live-buffers > (and (equal planner-tasks-file-behavior 'close) > (buffer-list))) > (timestamp (format-time-string "[ %Y-%m-%d ] " (current-time))) > (description (concat timestamp description)))
This will put a date stamp of the form [ 2004-12-17 ] at the beginning of each task. I had the time in there before as well, but it was too much clutter for not enough benefit.