Emails an HTML-formatted copy of a single post (not batch/digests) to site subscribers.
Select a post that's already been edited and saved, and that you consider finished. At the top right of the sidebar, you'll see a SoloMail checkbox. Select the checkbox and click the usual Update button on the post page. The email will be sent immediately to the group chosen in SoloMail options.
The checkbox will not remain checked - it's safe to edit the post again without risk of sending out mail again accidentally.
Only site administrators can send email with SoloMail. On multi-author sites, administrators can send other authors' posts out, as well as their own.