Why would mt gox. benefit from have the price higher?
That should be obvious. Assuming their revenue comes mainly from fees, a volume of 40000 Bitcoin a day translates to roughly BTC 200 / day, or $600/day. That's hardly the kind of revenue you'd expect from a healthy business. Revenue wise, MtGox is about as far away from the monopolistic corporation some ppl here believe it is as the bakery around the corner of the street.
the best thing for Bitcoin would be a slowly rising price from an infusion of money from either speculators, investors, merchants, whatever. an infusion of this sort would benefit everyone including the merchants b/c of the optimism generated. all the bashing of the hoarders and speculators would just vanish.