Looks remarkably like asana.com, flow.com, orchestra.com... Seriously, how did this happen? The UI, emphasis and core functionality of all these are so similar (even for a narrow category) that this cannot be a coincidence.
I can't speak to how those companies have built their products, but I can say that the inspiration for our product was Manymoon, and a three-pane view was always in the cards. It's a fairly straightforward UI paradigm used across many apps. I'm a huge fan of apps like Reeder and Sparrow, and they take this UI approach as well. As for the focus of the app, stay tuned :)