Is it really necessary for this service to have the ability to:

"View, manage, and permanently delete your mail in Gmail Create, update, and delete labels Compose and send new email"

I'm sincerely asking - it's not a rhetorical question. Does Gmail not offer more granular permissions than this?

Also: the other commenter's point re unexpected privacy leaks is a good one. I don't think I have any secrets that would be revealed through my correspondence habits, but I do so much email, I could be wrong. Do I have the ability to delete my info after I've registered if I don't like the service?

It's an interesting idea, and I'd like to give it a try, but without a little more assurance that I can trust them with access to my email, it's not worth the risk.