It sure is neat though! I love how the icons for each instrument can combine together, and the dynamic page title is fun.
Worth mentioning, since the post you replied to name-drops Dilla, that this renders it completely impossible to make a "Dilla"-style beat, let alone add any swing at all.
As typical though with anything related to web audio, it is neat one off parlor trick to show web programming skill but isn't worth the effort.
A circle is a compact way to make a useless quantized beat but if you want to take this further it will just end up reinventing the DAW wheel timeline. Otherwise, you have to have a sequencer for the circles, and then a timeline and then just get rid of the circles and have the timeline. In other words, a piano roll.
On another level, it is the coolness but uselessness of circular data visualization.