That map doesn't show anything happening on bitstamp whilst they report volume in excess of 100k and you can watch their live order book, dozens of trades of 10+ bitcoins happening as we speak.
Data from MT.GOX, BITSTAMP, BTCChina, BTC-E, Bit2c, Mercado Bitcoin BR, Local Bitcoins, OKCoin, BTCTrade, Huobi China, bitx.co.za, Cavirtex
Bitstamp is on the list so that is strange