[rplnt]

I'm not talking (just) about security. It's about convenience. It's annoying to go through million variations of registrations instead of approving the site with one click.

[blueskin_]

1. Enter username, and email address if not used as a username.

2. Enter password

3. Click link sent to email address.

Seems more convenient that having your privacy steadily eroded and introducing a SPOF.