We've got an existing 500 dev organization. People are slowly signing up. The process is, "hey, I want to send you a code review in Differential. Have you signed up yet?" If the answer is no, you have to wait for them to sign up and get their username.
It would be nice to be able to send a code review to someone who has not yet signed up. Probably by email address. That would just send them an invite.
Thanks!