Well,
To me, “Newsletter” means a wide range of functions : Create newsletters ? New post notifications ? a full featured Autoresponder ?
So many plugins are out there…
Any plugin that does NOT use it’s own wp-mail function (subscribe2 does not for instance) should work.
Plugin that uses their own custom mail librairies can’t just work without :
– editing yourself 1 or 2 lines of the plugin to use wp-ses intead of their custom method
or
– asking the plugin author to support sending mails via wp-ses.
That may be as simple as adding a singlecheckbox telling NOT to redefine wp_mail.
I’ll be happy to help integration of wp-ses with other plugins and add what may be needed to make that easy.
So, first define what your functional need is, then ask the author for wp-ses support. Then, I could test and list the working ones.
You can also “vote” in this thread for your favorite mail plugin that does not work with wp-ses, I’ll contact the authors and check with them.
Hope that helps ?