We've just released Processing.js 0.6, and with it a bunch of bug fixes and more WebGL-based 3D support. You can download it here, and read the full blog-post here. We had hoped to get a rewrite of the color implementation in this time, which will bring with it some nice performance gains, but that is going to slip to 0.7. If you're using Processing.js, please file bugs and show us what you're building.