Opt-in / opt-out: a big difference between Yahoo Groups and Google Groups

[Moritz Schroeder]

Doesn't look big, but the impact is quite significant.  Google Groups asks invited members-to-be to confirm the subscription, Yahoo doesn't, they  use the opt-out principle.

The opt-out method of Yahoo is interesting for real-world groups, where the group admins use the mailinglist to manage "passive" recipients of email.  I know a number of small local initiatives or political groups which work that way.  If you want to migrate your personal email list from the email application / client to a mailing list to benefit from more interactivity, economies of scale and more control for the recipients, you probably should be choosing Yahoo Groups.  If you chose Google Groups instead, you migration wouldn't be complete until all members have confirmed.

Regarding Google, I wish that the mailing list functionalities could be extended to Google Apps as well.  You can group users to email them with a unique group address, but it would be great to have an optional opt-in and opt-out  functionality...