A few months ago I wrote a Java websocket/socket.io client for Mt. Gox that processes the depth chart to explore my notions about depth and tick data. The ChartBuddy 3-D depth chart periodically posted here shows the time dimension like I wanted - so no point in going further. But I did learn enough about the Mt. Gox API to very deeply appreciate the cleverness employed by Clark Moody who ties together Mt. Gox trades and depth changes.
I wanted to do the socket.io thing (and still do for another project) but found it poorly documented and jumped on the http in the end. I still need to figure out why I appear to be regularly missing the first few minutes each hour from Gox. It's not always but it's often enough to be annoying.
I use the Chrome web browser. Its tools permit the monitoring of the TCP traffic between client and server - and so I watch Clark Moody's app to confirm the socket.io API that Mt. Gox uses. I likewise found Mt.Gox performance to be annoying.