Pandoc recently added read/write support for "admonitions", which are a GFM construct already supported by other org-exporters, and on GH in markdown. This refcard references an org #{begin,end}_{note,warning,tip,caution,important} syntax which pandoc now follows (though it does not support the extra admonitions like danger/error/etc.).

It would be nice to add org support for these 5 admonition blocks to the C-c C-, org block structure templates, and perhaps allow block face styling for these as well (ala org-src-block-faces).