What will be the BTC price on other exchanges if mtgox price goes to 0 ?
We're unlikely to see the price of Goxcoins fall to 0. Instead, Gox will just be taken offline. The world of real bitcoins will be affected by Gox's death, but I don't think the real bitcoin markets are going to follow Gox down much further and at some point it will be clear that the real bitcoin markets have moved on.
Yeah, the Mt Gox price is increasingly detached from other exchange price and if Mt Gox is not going to allow withdrawals, trading bitcoins there does not make sense so the price is not that likely to go to 0. I think they may just temporarily stop trading and then perhaps shut down the whole enterprise?
OTOH, if Mt Gox goes bankrupt, it will be another remainder how risky trading bitcoins is so prices elsewhere would likely go down and institutional investor may stay away for a while.