Comment 1 for bug 1265086

Hidden "Overdue" / "Completed" as alt text for the image would be better than "yes" or "no" imho because it's more descriptive esp. when you have a long list and don't want to go back to the top of the table to read the column label. I would go for "Overdue" instead of "Incomplete" because when the deadline hasn't passed yet / the completion date been reached, there is no icon in the table cell. You only see an icon when you marked the task as completed (green checkmark) or when it's overdue (red warning sign).