Man I LOVE the redesign. This is better IA, better UI, better UX overall.
One small but significant nit: As I've used the tool consistently since the redesign, I've noticed that every time I go to add a new task I have to look around for the "add task" button. It happened again just now. The placement of the button is right, but it looks too much like a part of the inner-header.
Once clicked, the button state changes to "cancel", and a new "add task" button appears below all the task details for submitting the changes. That second "add task" button is orange and easy to see.
Consider making the initial "add task" button orange. It's by far the most important user action on the page - especially for new users with a blank slate. And the initial and secondary submit "add task" buttons would then be linked because they would share visual treatment.
As a UX designer with a dozen years experience, I wanna chime in with "THIS ROCKS!" Great job! I was startled at first by the changes - especially flipping the top and left navigation regions. But it only took 3 minutes of exploration to get comfortable. Everything is easier to find and use.