IE and or any old browsers can support canvas tag when you use ExplorerCanvas http://code.google.com/p/explorercanvas/

So IE not supporting canvas tag 'officially' isn't really a problem.

EDIT: Just found that ExplorerCanvas has a new home at soundforg. Download here http://sourceforge.net/project/showfiles.php?group_id=163391

I doubt the possibility of emulating canvas tag in ie using this technique, because its very limited compared to canvas (for example, its not possible to draw lines).

This technique can bring cross-browser support of drawing polygons.