> Threads won't be able to share FBO's or VBO's, but we're working on SharredArrayBuffer, which will allow multiple threads to share data (more like C style arrays than JS style lists, they still would have to be glBufferData'd to VRAM from RAM).

It would be amazing to have fast GPU-GPU transfer. Is it the case in Firefox that using texImage2D/texSubImage2D on a main thread context with a worker <canvas> will result in a guaranteed GPU-GPU transfer? Or does that download the pixels to the CPU and re-upload them?

> Isn't that the case for all applications?

Yes, but I haven't been following GPU tech recently so I wasn't sure if that still applies universally. Maybe some day we'll get preemptive multitasking on GPUs :)