Email Templates /Queue

OK, so that I understand... in the admin (Email Templates) at the very top of the page it says...

"Send emails from queue, it happens every cron execution (5m-1h)   (and then there is a number "20" in the box)".

Does this mean that cron will execute and send out "20" of the emails in the email queue every 5m-1h until all emails have been sent?

Just want to understand this correctly... don't want to upset my ISP with too many emails going out from the site all at once.

Thanks!

Anyone know the answer to this?  Or better yet, does anyone know if the mailer sends them ALL at once... or are they sent 20 at a time until they are all sent?

I have over 1,000 registered users and it would definitely be considered spam if they all went at once.

i have the same problem. Can anybody answer?