It is always shocking to see how easy the price can be manipulated. Without any volume the price went up 50$ in minutes. As the price was at 840$ somebody bought 13 coins for 895$ each and bang there we are now at 884$...
You're looking at the wrong exchange. The volume on the runup was huge on btcchina. Also: we had just come down through that area, so asks are weak.

Indeed. People keep forgetting we're now working with a lot more exchanges, and how much the volumes have changed:
btcchina 64392.620
mtgox 14323.340
bitstamp 11403.840
btce 11393.550
check out these other two chinese ones which are seldom mentioned:
okcoin 42990.150
fxbtc 21509.410
wow! Those 3 china-based exchanges account for 147,000 BTC volume? That's 10 times gox!
I know, I know... no fees. Maybe time for the Western exchanges to lower fees, too?
What timeframe are those volume numbers?