I had some experience with gameQuery and made a side scrolling jump and avoid game for a company in the UK. I learnt a lot and had great fun doing it. The gameQuery engine provides basic sprite sheet animation (you are limited in sprite sheet layout), layers, a game loop and some basic collision detection (bounding box only). It targets the DOM and ties you into it heavily which may not be what you want. I gather other libraries allow you to switch implementation?
I agree with jhocking in that you should leverage as much pre-written stuff as you can. LimeJS comes with a javascipt implementation of Box2d, the engine that was used to make Angry Birds. I can't really comment on Google Closure but if its good enough for Google its good enough for me.
