So, why would I trust you with 5 years of all my sent and received emails? Should I take your word for it that you'll just save the email addresses and the sent/received timestamp for each?
Ideally, I'd like to see unsecure e-mail replaced by crypto communication systems based on OTR and people locally storing their emails on Raspberry Pis, but that's dangerous stuff and I probably shouldn't have even said that.
Thing is, I'm sure you're nice guys and gals right now, but when you're billionaires and have 500 million people's digital data, evil you will turn.
By the way, good presentation at SVNewTech last night.
Those are the gotta-haves. If you provide a secure clearinghouse to talk to our clients and vendors, that would be a major selling point. It has the chicken-and-egg problem, of course, but also the network value effect.