The price on MtGox is $238, $634 on Bitstamp, $400 less! There is a lot of speculation on why the price is so low. Some speculate that everyone stuck in MtGox has been moving to cash. That's possible. But, the opposite is also possible.
If everyone buys BTC inside MtGox, eventually, you run out of buyers. Let's imagine that very few have cash in MtGox. Now, when someone tries to sell it, the price will drop, because the few who still have cash are not willing to buy at all or at least not buy unless it is cheap.
In this scenario, if the majority possess BTC, and a small percent of them want to sell, you can still very easily have more people willing to sell than buy. E.g., let's say 95% is in BTC, and 5% is in fiat. if 10% of the BTC holders want to sell, that is still double the amount available in fiat.
In short, MtGox is currently suffering a massive liquidity problems. Since no one can buy or sell items with their currencies in MtGox, other than currency itself, you eventually run out of liquidity to support trading. The price will naturally move to one extreme or another. Previously, where liquidity was limited but you could still get money, especially BTC, in and out, the price was abnormally high due to the restraints on the fiat side. Now, that BTC withdrawal is plugged, it is abnormally low.
Add to this that those with fiat now have an incentive to wait to see how low the price will go. Like a dutch auction, they are risking that opportunity being gone forever in the hopes they can get the best price.
Does not sound right, because lots of people have fiat currency on Mt. Gox. Why? Because they cannot get it out.
I also find the Gox prices ridiculous. My explanation is that there are many users who are simply uninformed. They have not read the forums or the Mt. Gox announcements. They are panicking.
I guess we are hitting the bottom around now. I think the price cannot go down to $200 while it is $600 on the other exchanges. There must be some people with some reason who buy at prices below $250.
Moreover, Mt. Gox will issue another announcement tomorrow, which will influence the markets. If it sounds positive, like stating that bitcoin transfers will be switched on later this week, then the price on Mt. Gox will rise. The price on the other exchanges should fall somewhat, but perhaps these considerations are already partly reflected in today's price, which has gone down a bit over the last few days.
The people I know with balances in MtGox are in BTC, because they thought they were buying low when it dropped and consider BTC withdrawal the only viable option -- their international wires were taking over a month prior to this fiasco. As much as they wish they held out and bought at $250, they can't, just as the vast majority of us can't just inject fiat into our MtGox accounts and buy at this price either. If you bought BTC at $500 in MtGox, and you are informed of the news, events and issues, you are likely holding.
But, in the scenario I described, you would have to have a % of BTC holders wanting to sell... which fits your description of uninformed people panicking. So, in that regard, we're on the same page. The only difference is that if BTC balances are 20x fiat balances in Bitstamp price terms, then liquidity on the buy side is just critically low. With no way to infuse fiat from the outside, you can't raise it short of selling your BTC at a price that 90% of BTC holders probably realize is ridiculously low.
If I could get fiat into MtGox today, I'd do it in a heartbeat and buy as much BTC at $250 as I could. Unfortunately, I can't.
...Have a towel handy. 