Weekly chart is more clear to read:
Compare the two blue periods. The second one has slightly lower volume, but the price is three times bigger.
Compare the two orange periods. The second one has similar or slightly lower volume, but the price is many times bigger.
What does it mean? That price and volume aren't that much related.
I understand the rationale of many forum posters here contending that volume does not go up as price goes up. However, whatever experimental evidence we have does not seem to support this assertion.
It's actually the other way around. The recent price raise was because of increased demand, which created bigger volume - as there were many new people wanted to buy-in, the price raised. But price and volume aren't related that much. If more people wanted to sell than buy, the price would go down despite having big volume.
Let me give you an example.
If there are 10 people that want to buy 1 BTC each and 50 people that want to sell 1 BTC each, the price will go down as sellers will compete for the buyers. If there are 5 people that want to buy 1 BTC each and 1 person who want to sell 1 BTC, the price will go up, as buyers will compete for the seller. You can have increasing prices at low volumes and decreasing prices at high volumes. Or the opposite. Price is the result of the ratio [how many people want to buy] / [how many want to sell]. Volume is just [how many people want to buy and sell]. With people wanting to buy 10,000 BTC and other people wanting to sell 10,000 BTC, the price will most likely won't change. With people wanting to buy 10 BTC and other people wanting to sell 1 BTC, the price will most likely go up.
Price, volume. Not related. The only thing connecting the two, is that when volume significantly raises, the price usually changes a lot. But it can change up or down. MtGox doesn't care that much if the price is high or low. They care for the volume. They're as much happy with people creating volume by panic selling as with people creating volume by horny buying.