My observation is that 'email' is now a lot more common than 'e-mail' online, and Wikipedia corroborates this (https://en.wikipedia.org/wiki/Email#Spelling).
I think this will make people feel just a little more comfortable, so I propose changing our standard to be 'email'.
I don't think this is an American/British issue, since the Oxford dictionaries have 'email' canonical too according to http://oxforddictionaries.com/definition/english/email
Version: 1.21.x
Severity: enhancement