The server had a hard time dealing with the load. I suspect running node.js on Cygwin contributes negatively in that regard. Furthermore, my custom serverside canvas could probably benefit from being asynchronous, and the server really should batch up updates within a certain time frame, to not hammer other clients.
Neat! Though, on Ubuntu with Chrome 9.0.597.98 I never got loaded after 2 minutes. This could just be due to traffic load though. However, I was able to see other people scribbling, which was still fun.
The server is being hammered pretty hard at the moment. It's taken on 30-40 simultaneous users before, and worked without a glitch. Now it's around 50, and a few seem to be going beyond the normal update rate.
At some point I will have to enforce a harder rate limit, and/or build better spam protection. The app has been pretty much unused for the last 5 months though, so there hasn't been any real reason to focus on that part :)
Sorry about that. FF has websocket support disabled for now, and I've been slow to move to socket.io. That, and plenty other updates, are in the works. :)
Some strokes have huge lag during spikes, others that I made on my screen are never displayed on the other tab.