I think Chris sums it up nicely. Email applications need to be more open and configurable. I don't believe email is broken, as some people like to say, I think it's just how we interact with it that needs fixing.
At work I've taken up portions of Merlin's Inbox Zero and it's changed my work day entirely. I reply to anything that needs replying and I am on top of many conversations. On Friday I left the office with a completely empty inbox. Heck, my Mom even noticed I reply to her promptly.