I fail to see how this is different than a Wordpress private blog.
> Private. Select this option to make your site private. If you want specific people to be able to view it (and add comments, if you’ve enabled them), you’ll need to invite them to be a viewer.
> Private. Select this option to make your site private. If you want specific people to be able to view it (and add comments, if you’ve enabled them), you’ll need to invite them to be a viewer.