Each time a buy order was filled it was announced. So you could see the price fall as buy orders got filled. Did the YouTube video show the time stamps on the trades? If I recall correctly every single buy order that got filled had the same time stamp.
Hmm, this makes sense. But, I still think that the ticker should be updated after every trade. Although this was one huge sell order, it was filled by many small buy orders. From the perspective of the buyers, those were 'trades'. Why should one end of a trade be given more priority over the other end with respect to the ticker?
Anyway, thanks for the responses. I feel better about trading on Gox now.