Image via WikipediaSince there is only one item on this list, it's not much of a list. When I first looked at Gmail, the nestled conversations drove me crazy, but the more I used it the more I came to love it. I can find information easily because I tend to remember subject lines to search for. I've even integrated it into my daily routine with Things to provide easily access to emailed task I need to accomplish.
I've learned the keyboard shortcuts to make gmailing easy for me including archiving that not-so-bacn and, when managing huge boxes, deleting a lot of emails not needed quickly. The keyboard shortcuts save me a lot of time that normally would be roaming around with a mouse or trackpad. While Gmail has and continues to improve it's speed, it's not nearly quick enough when I write an email, send and have to wait to then archive the email after I've responded to it. I'm not a strict GTD fan but some methods are important to me.
One thing that I've discovered is I really really really want a send + archive shortcut. If I could hit enter+tab+someotherkey to send and archive all in one step I could move on to my next email without waiting for it to send then archive. While I realize I could send and come back later to archive, I usually process my mail in one batch. I want to quickly send + archive then respond to the next message.
I'm sure there's another way such as moving through all the emails, responding and then archiving at the end. I have all the love for Gmail and it's developers and respect that they have time to work on specific projects to make Gmail better, but these twowould kick up my productivity a notch.