Recently stumbled upon this one: attaching an image to an emailed-in post makes this image appear in the post, but only if you’re not using markdown formatting. When using markdown formatting the image doesn’t show up. Not a big deal if you’re aware of it — simply mail in HTML or plain text.
Funnily enough the image does appear in the edit view of the post (which makes me suspect that markdown is rendered at the output, and the renderer won’t handle attached images).
And an (even smaller) buglet: using HTML to embed images in mailed-in posts will result in two images being shown. Apparently posterous groks the content-id syntax (which is a great feature btw.) but thinks the image attachment should be shown separately, even though it is already referenced in the HTML mail.
Both of these are quite harmless as workarounds are easily available. Its just a pity that they’re not documented (at least I didn’t find anything), so the users have to figure this out themselves.
