It is impossible to know Mt.Gox's liquidity position at this moment, but there are things we know for certain:
1.) Mt.Gox's US entity, Mutum Signum had its accounts frozen. More than likely a large portion of their USD revenue was tied up in that Dwolla account. They may or may not get these funds back. I would expect they would have to get their Money transmitter license in all 50 states before these funds could be released. That would take at least 12 months and $2M in fees/surety bonds(1)
2.) No one has gotten a wire out for almost a month, if they had they would have claimed the 0.75 BTC bounty.(2)
3.) Bitcoin holders are willing to take a 5-10% cut just to move their BTC out of Mt.Gox. That's the reason why the spread is so large vs. Bitstamp.(3)(4)
4.) Legal defense is expensive. They are fighting 2 fronts, one with Coinlab, and the other registering as an money transmitter in all 50 states. They will lose the case against CoinLab for $75 MM. Even if the outcome looked more positive, no bank would lend them money given the uncertainty of the outcome of the suit.(5)
5.) Volume is at January lows, their trading revenue won't be enough to cover both legal fronts and operational costs.(5)
6.) Mt.Gox consistently releases confusing and contradictory information, so their "official" statements have no value.
7.) Mt.Gox used to exchange liberty reserve dollars. Any entity touching LR dollars has serious going concern. I can assume they will have some legal issues with this as well.
With that being said, there aren't many explanations that fit. But even if Mt.Gox collapses, you still have rather large markets with Bitstamp, Coinbase, and Btc-e, which should be able to provide enough liquidity/volume until some US exchanges become compliant.
(1)
http://thegenesisblock.com/town-hall-discussion-with-gavin-andresen-and-patrick-murck/(2)
https://bitcointalksearch.org/topic/025-btc-bounty-show-me-a-mt-gox-usd-withdrawal-251895(3)
http://bitcoincharts.com/markets/(4)
http://thegenesisblock.com/bitcoin-mid-year-review-and-outlook/(5)
http://thegenesisblock.com/mt-gox-withdrawal-freeze-driving-significant-liquidity-concerns/