There main difference between this case and Madoff, is that the trades actually happened, and people were making their own trading decisions.
I don't know what the court
will say, but they
could say that the people were trading non-existent coins, so the balances are meaningless.
Actual deposits and withdrawals are numbers that the court can verify with the banks and in the blockchain. The trades inside MtGOX are recorded only in Mark's database, and any information that comes from him must be treated as a mere hint that needs independent evidence to be trusted. The database may have been doctored to give large bogus balances to some clients.
Nope, trades were published in real time, and more or less complete records can be retrieved from many locations. The only unknown is which accounts the trades belonged to. Faking account balances afterwards by switching which account did the trade will require a lot of work to make everything match up, and even more to seem credible. Not sure if it will be possible at all if everyone will be allowed to verify their own data. People have already been able to verify their balances for a while, and I haven't heard of an complaints. An audit will trivially reveal if the trade data matches the balances caused by deposits and withdrawals.