> This is something I see happening perhaps a few times a week
> if the whole world used C/R.

Please, Brad. Hotmail, Yahoo, AOL, etc add something like several hundred accounts to their service an hour. There's no way CR is going to ever keep pace with it. Even after using CR as a last layer of protection against spam.

http://www.hserus.net/images/minute.png - that's about a million emails a minute rejected, and 100k emails a minute accepted / passed by our filters. Now, even if a fraction of those incoming emails were greeted by CR ... and our mail farm (with 40 million users) is barely a third the size of AOL's.

NO way CR is going to scale in such a situation.