I followed your tutorial and got briefly hung up by an error saying that Canvas wasn't defined. Turns out I was running it on the newest version of Meteor, and in 0.6 they started putting local variables at the top level in an IIFE. Functions declared using the named function syntax (function name() { ... }) are locally scoped, as far as I know. I fixed it by changing it to Canvas = function() { ... }.
Other than that small problem, cool article, thanks!
Other than that small problem, cool article, thanks!