As I see it, there are three ways the Mt. Gox fiasco could play out in the short term:
(1) Mt. Gox announces in a week or two that they have finally fixed all of their issues, and are completely reinstating BTC withdrawals.
(2) It becomes clear that Mt. Gox is completely broke (e.g. it had a massive theft of BTC by insiders, was hacked, etc), and will never reinstate BTC withdrawals.
(3) Mt. Gox drags this out for another month, and then only reinstates very limited withdrawals with a small cap on daily withdrawals.
My predictions:
(1) If Gox actually fixes their issues and reinstates BTC withdrawals, the price on all exchanges will increase significantly. My guess is that BTC would shoot up to the $700-800 range within a few days, because a true fix would provide a huge reassurance to the world at large on multiple different fronts. First, it provides reassurance that the BTC protocol is not fatally flawed in some way (of course, anyone who knows something about BTC realizes that was never a real risk, but the distinction between transaction malleability and a core protocol issue is too subtle for most non-techies). Second, a fix provides some reassurance that BTC isn't something that is just too complex and esoteric to gain wide acceptance (i.e. some people are probably thinking "well, if Gox can be brought to its knees because they overlooked some little technical detail, that kind of thing is probably going to happen many more times in the future, and crypto is just never going to be able to go mainstream).
(2) If Gox is defunct, BTC will decrease significantly. The market is already factoring in this possibility to some extent, but based on the exchange rates on bitcoinbuilder, it seems like the market consensus is putting that likelihood at less than 50%. Plus, I am not sure that the market has yet fully factored in the potential snowball effect of lost confidence in cryptos generally that could result from the complete collapse of Gox.
(3) If Gox keeps dragging this out, it puts some downward pressure on price, but not so great that it couldn't be overcome by other news (e.g. favorable announcement by a government or a very large retailer).
I hear a lot of people saying that if Gox reinstates withdrawals, the price is going to go down because of the huge number of current Gox users that will suddenly be able to sell their BTC on some other exchange for double the price. However, I think that reasoning completely overlooks the massive upward pressure on price caused by increased confidence in BTC generally, and also wrongfully assumes that a large portion of GOX users will suddenly want to cash out to fiat (rather than simply holding on to their BTC in a wallet or on some other exchange).