One thing, and I have mentioned it before, that I find very annoying is the way the check boxes work. I get many email, I check 10-15 at a time to move/delete. If I misclick, which I tend to do too much, it unchecks everything I checked. Typically what will happen is I will click and instead of hitting the box I hit an email which unchecks everything and displays the email I clicked on. I do this all the time in my gmail and it keeps the check boxes checked