I recently (I know I'm behind) read your post regarding the re-design. For the most part I really like it. Here is one suggestion:
I read that the "tabs" had been moved to the side. I looked on the "Before/After" screen shots and saw what you meant. However, I realized that since using the new design I never thought of them as "tabs" because they don't LOOK like tabs.
My suggestion: When a side tab is selected, make it the same color as the task area with no line in between. Also, round the left-most corners. This will make it look more like a "tab". In other words, make the side tabs look just like the top tabs of Tasks, and Notes. Keep the sizes the same, but just use the colors, corners, and shading when a tab is NOT selected the same as you do on the top. I hope you got what I was trying to describe.
2nd Suggestion: How about scrolling the task area and keeping the toolbars, etc. at that top from scrolling. So when you have long list you can scroll to the bottom and still have all the tools, sidebar, etc. available. Like a "freeze panes" in Excel.