Doesn't make sense to me that wealthy people would be buying up and driving up B, just because the community desires that. Right now, it really does look like a great speculative investment, and new buyers are arriving in the market...
I didn't say wealthy people are buying because the community desires it? I'm just saying that those big jumps in value in a matter of minutes were created by single actors.
Also why do you say it doesn't look like a good investment? People who bought bitcoins at the start of this thread have had over 1000% return on investment. I'm think most would agree that bitcoin growth will be outpacing any other commodity/currency for a long time.
While the big jumps were by single actors, I would argue that doesn't tell the whole story. Mt. Gox does represent the bulk of the community and it has been impressive in terms of how many people are participating. Generally I've been watching how many users are involved, and it typically has been about 50-80 people with orders on the market at any given time (the operator of Mt. Gox could give a definitive response for the exact number). There are also other "lurkers" like myself who stay out of the market at the moment.
What is interesting is that I've been spending most of my time also watching the Ruble market on btcex.com, where actions on Mt. Gox are typically reflected on those markets too. Sometimes there is a bit of a lag, such as how the WMZ market is a bit below the Mt. Gox price, but I wouldn't bet on it staying that way for too long. Hint: If you can change Liberty Reserve for Web Money, now would be a good time to do just that and get some Bitcoins for cheap from that particular market.
The Ruble has long ago passed parity, but the current exchange rate is roughly settled down at what Mt. Gox has if you converted Dollars to Rubles on the ForEx market. While it doesn't have the volume of Mt. Gox, I would say that this is a good indicator of what other traders elsewhere think of the value of Bitcoins.
The value of a Bitcoin is going up because those with Bitcoins don't want to sell them for cheap. It is certainly a genuine auction market where the supply of Bitcoins is limited, but the supply of other currencies is plentiful. If there were piles of Bitcoins burning holes in people's pockets, they would be put onto the market at this time. Anybody who has either purchased or mined a Bitcoin could at any time put in a bid for a lower amount. The real issue is why that isn't happening, thus pushing the market up. Those who purchased Bitcoins for smaller values in the past certainly could use this opportunity for some "profit taking" into Dollars/FRNs.