If there were a way to auto-send e-mails to new members when they have been accepted to the guild, there may be a way for it to indirectly help retention by getting people to un-check the 'Don't send me e-mail' box, thus being able to receive the other automatic e-mail that notifies them that they are being inactive, or being booted for inactivity.  If we could customize this e-mail to say something like, “Welcome [username]!  You have been accepted to [guildname].  Please visit the site and join the party!”  Now I realize that this won't really help retention by itself, but, if done right, it could help members not check their “Don't send me e-mail” boxes.  For instance, when I first joined a Guild Portal guild, while I was filling out my application, and on the application it said, “Don't check the 'Don't send me e-mail' box, as you will be recieving confirmation of your acceptance through an automatic e-mail.  We promise we won't spam you!” I probably would have left the box unchecked.  I realize that there really isn't a way for a guildmaster to force people to uncheck that box, but some incentive would help.  I think that a standard acceptance letter could do just that.  I bring this up because, since enabling the feature for sending auto-inactivity/boot notifications (which I think are a good idea), our guild has auto-notified approx. 25 members for inactivity.  Absolutely none of them have recieved this message, as they all have had the no email box checked.