Yeah absolutely if SendGrid builds this functionality and creates a 'Welcome Mandrill customers' page, then you guys will get a whole heap of new signups right away!
Agree 100%.. this is an insane move by Mandrill and if SendGrid can at least show email subjects they will reap the benefits imo !
We're discussing what it would take to build it right now. It's absolutely one of the things people appreciated about Mandrill, and I know we want to ease the transition as much as possible.