Actually, I've got the same issue Barry. My site collects signup information from new members, currently at just under 30k. And they are free to specify whether or not to receive any emails.
As Barry mentioned, I too would like to send an email to each of my members (who have agreed to accept emails), but the contents of each message is a little different, based on their account info, yadda yadda. In the past, I've used a PHP script to send out each custom email, one-at-a-time, using PHP's mail() function. However, I realize that doing so puts a large load on the server, so I have always tried to stagger it - maybe pausing for a couple of seconds after every 30 to 50 emails.
You mentioned using DH's "Announcement" system, what exactly is that? A regular mailing list is not quite appropriate since each email is customized for that particular member. I really don't want to affect the load on the server too much, but I also want it to be convenient. Any more ideas?
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