After a couple hours of beating my head against the wall and trying different DOCTYPE declarations, I finally figured out that it was in fact the lack of <canvas> that was my problem. A co-working pointed me to ChromeFrame. This nifty little script looks at the browser that’s loading a page and, if it’s IE that doesn’t support <canvas> (and other things) it throws up a warning and offers to install a little utility to help you out. Once you say ok, everything works just like it’s supposed to. Pretty good time saver. Not sure why everyone doesn’t just install it.