After a bit of time using the site I can see people using lots of nice equations. But there's nothing in the "How to format" help box (or in the "full reference >>" link) saying how to do this.
I got a couple of comments like "use $$ around your equations" but that didn't actually work. I guess I had the format slightly off or something. I've not used LaTeX before either so didn't naturally know what to do. I think it would be a great help (especially for newbies) to have a single line in the "How to format" section saying something like "Enter formulas like this '$$ \pi $$' - see for details of how to do this better" with a link to a LaTeX reference.
I think the current feature isn't very 'discoverable' unless you already know about it.