And I also find that maybe MtGox has cached the json data, since whether I use php curl or Chrome browser directly , I cannot get the trades executed in last 10-15 seconds . Instead , I always get the trades executed 1-3 minutes ago. And users watching the realtime trades data complain about the delays. 2-4 minutes is just too long.
So I guess maybe MtGox has cached the trades data for 2-3 minutes. Tux , would you please give some specification on that?