[hartleybrody]

What a perfectly obtuse, technical solution. Is grandma going to solve a captcha in order to sign up on a wordpress blog to view photos of her grandchildren?

Dropbox is "just" a private s3 bucket with s3cmd on a cronjob -- or a million other technical solutions -- but they're a successful business because they nailed the user experience for average joes.

The point of OP's product is that you don't have to cobble together a bunch of hacks to replicate the desired user experience, it's supported out of the box.

[dataexporter]

Wordpress lets admins create accounts and set passwords for the users as well. One can quite easily disable public signups (to prevent spam) and manually create an account for one's grandma.

For public signups it is a perfectly valid solution to use captcha!