Have a look at this answer.
I see the text
![Phone Types on Outlook.com][2]
rather than the image he is trying to display. But when I clicked "Edit" to fix his formatting, I found that the image was correctly displayed in the preview pane (see below).
Either this formatting should work in neither the live question nor the preview pane, or it should work in both.
The moral of the story is:
Don't intimately mix Markdown and HTML in the same narrow block of code, because Markdown being a regex based solution will not know how to treat some elements.
Which should tell you exactly what happened to the post in question. The parser got confused. Technically when the markdown parser encounters HTML it should quit parsing the HTML block, or what it judges to be an HTML block.
What's more, there are plenty of hinting shortcuts just above that tell you how to make things format certain ways in markdown. Just do everything in markdown. It's easier.
The client-side and the server-side Markdown implementations differ.
This, combined with the fact that the list wasn't formatted using Markdown, broke the image, I guess.
