The USD withdrawl issues are slowly killing gox in the USD market.
The current visible USD buyer depth is a little over 40,000
BTC and centered at $136.5 (
http://bitcoincharts.com/markets/mtgoxUSD_depth.html). July 30th, that depth was at 70,000
BTC (
http://decentralizedhashing.com/2013/07/july-30-bitcoin-price-update/), which means a depth drop of approximately 25% in less than 2 months if you convert the depths to USD.
Looking at the historical data (
http://bitcoincharts.com/charts/mtgoxUSD#rg90ztgSzm1g10zm2g25zv and click 'Load Raw Data'), there has been $217,693,425.40 worth of trades since July in the last 3 months (mid-June was when withdrawals started having big problems). Assuming .6% USD was taken out by each trade (actually up to 1.2% if you consider both sides, though for heavy buyers it would be lower due to the fee schedule), that means $1,306,160.55 has left the trading system.
Likewise, the Average daily trading volume is dropping (in USD):
June: $3,689,480.02
July: $3,183,861.17
August: $2,196,336.10
Sept: $2,172,255.06
Look at the major drop in August as people realized that "USD withdrawals resumed" was a huge stretch of the truth.
Also, as for Gox's cash-flow, would you deposit USD into Gox when you don't know if you can withdrawal it? NO! On top of that, their price/
BTC is way higher! That is a formula for zero USD into the system.
However, cash IS flowing out of Gox (at least out of available trading funds). How? Why in trading fees to Gox! If you assume .6% for each trade (could be up to 1.2% if both parties are considered and there are no rate discounts) and no deposits since the beginning of July, that means $1.3 million less in the USD trading depth users have to work with.
For these reasons, if I were Gox my number one priority would be getting USD withdrawals back online. If they do that, USD will start flowing for them again,
BTC price indexes would include them again, trade volumes will rise, and thus their profits will go up. However, MAJOR damage has been done, as they have left gaping holes for other exchanges and have lost the faith of most of their USD customers.