Kapow, we have schemas for snippets, making it vastly easier to define additional fields with no client side code and just a few lines of json on the server side! You still template it out in new.html, to maximize your control over the look and feel.

You can still do it the old way, except for the enableBody and enableThumbnail methods which have been superseded by the new addFields and alterFields options to the constructor.

TODO: document this so people no longer suffer subclassing snippets the hard way.