When bitcoinica is about 75 percent of mtgox volume and its mostly on margin, for such a small market, and routinely runs out of head room in whatever direction the market is going, explain to us all in detail how you think it helps..
Bitcoinica was usually ~10% of MtGox volume until Jan 14th, the day Zhou offered a no-fee day. This was like a banker yelling, "Free money, one day only, come and get it!". The expected happened: he ran out of reserves. I hope he learned his lesson.
As others have pointed out, the problem isn't leveraging, it's
excessive leveraging. And by offering 5:1 and 10:1 leveraging, Zhou does a disservice to his community.
Im not saying leveraging is the problem, Im saying that ALL the leveraging is done on bitcoinica, which is essentially, when it gets down to it, goes onto mtgox, when bitcoinica gets to a point that it needs to change its position, this causes the wild spikes, which is made worse by the excessive leveraging like you said.. No offense to Zhou, but you guys realize hes making the most when these momentary spikes causes liquidation. (Zhoutounged)
Mtgox price being the defacto standard in the community is the problem, and bitcoinica is just adding to the volatility of mtgox. We need another exchange with high volume, bitcoinica has the potential to do this, I hope they do this someday soon.
Then and only then will we have the starting of a buffer for the market.
In other words, the excessive leveraging on bitcoinica that all transposes down to mtgox is making things worse.
Edit - I should note also, I have never been liquidated, and actually have made 22 dollars from bitcoinica in the few times I've used it So Im not biased because I've been hit hard ..