I can't seem to find a combination that works in all cases.
I needed to turn on the Jetpack shortcode embeds for backwards compatibility with old posts. And I needed to turn off the Auto-hyperlink URLs plugin because if it was on it messed up the display of YouTube embeds that were in old shortcode messages.
But I'm posting without shortcode embeds. For example, the message (http://douglerner.net/?p=2399) contains:
If I edit the post and look at the html it is just that.
But Subscribe2 sends a message with the raw source including an embed tag and a flash player call, so in Mail it just shows up as a black square.
Yes, WordPress itself is rendering it that way in the web view at the site, but internally it just contains the above URL.
So why does Subscribe2 send out the embed tag? Why doesn't it just send out the URL as entered in the post?