For the last hours I say we are doing fine without mtgox. Mtgox should never reopen or it should reinvest all it's profit to re-enable trust that they crushed.
We have no way of knowing.
Mt. Gox says at
https://support.mtgox.com/entries/21519569-Market-Cooldown-for-12-hours:
"However, you may still cancel your pending and open orders."We have no idea how many "pending and open orders" Mt. Gox has yet to execute. There could be hundreds or even thousands.
Also, what kind of viable currency would allow an exchange that controls 80% of the market to declare a "market cooldown" whenever it pleases and for however long it pleases?
If you have access to another exchange, you'd better give serious consideration to what could happen 5 hours from now.