See [Pandoc's Markdown](http://pandoc.org/README.html#pandocs-markdown) that has everything. Will add all pandoc extensions over the next couple of days to the Can I Use ___ ? site. Cheers.

PS: To quote:

Extension: implicit_figures

An image occurring by itself in a paragraph will be rendered as a figure with a caption. The image’s alt text will be used as the caption.

Extension: table_captions

A caption may optionally be provided with all 4 kinds of tables. A caption is a paragraph beginning with the string Table: (or just :), which will be stripped off. It may appear either before or after the table.

And so on.

I don't know if this is how you'd do it in markdown. My text tables are generally done this way:

    +-----------+-----------+-----------+
    | label a   | label b   | label c   |
    +-----------+-----------+-----------+
    | r1f1      | r1f2      | r1f3      |
    +-----------+-----------+-----------+
    | r2f1      | r2f2      | r2f3      |
    +-----------+-----------+-----------+