It really helps to be able to automate workflow based on whether work is being blocked. I would argue it is also critical to know what work IS BLOCKED as well. In some cases users might not be able to accomplish a task that is upcoming, due or overdue because the dependency is blocking the task. In some of these instances the user might have influence on the dependency and could help get the task completed so their responsibility is unstuck and ready for action. Furthermore, I have seen where many users like to group tasks that are “pending” or “blocked” within they My Tasks or other Projects.
The ability to automate actions on tasks (like moving to a BLOCKED section) would be really nice. Because Rules don’t seem to execute in any particular order, the workflow attempted in the following post fails unfortunately - Allow user to define a specific order of rule execution - #5 by Jerod_Hillard
I think introducing some NOT condition triggers would really strengthen what users can automate. NOT blocked might be the most beneficial for me but I can see where others would also be useful (e.g. NOT in section or NOT with a due date)