- Width (& height) should by default derive from the parent Raphael object.
- Allow setting popup=false, so that no hover function would be defined, thus making the lines1 and lines2 data attributes optional.
- Allow defining a custom hover function, that I would bind to the rect/circle objects.
- Test in IE, add "tested browsers" list to docs (so far success with Chrome, FF4, Mobile Safari).
- Fix IE bug: getElementsByClassName undefined.
- Allow liquid width/height (how?).
- Reconsider setting drawGrid and popup as Raphael plugins.
- X, Y axis ticks near labels