they refunded/creditied me my unpaid withdrawals in about an hour from contacting them.
I find it very interesting that MtGox support is totally useless and give copypaste answers when asking about USD withdraws. If you just ask them if canceling a withdraw is possible then they go ahead and do it almost immediately if even if you just asked if it's an option and did not specifically ask them to do it. They seem
very eager to have customers/suckers buy their over-priced BTC instead of sending them their USD.
Of course they are willing to do so, the more people buy their already overpriced bitcoins and sold them on Bitstamp, the larger the price gap between the two exchanges, the more profit they could make from doing arbitrage between the two. As the only USDs that could leave MtGox now is their own dollars, they have a monopoly on doing this. They could earn 10% profit doing every round of arbitrage. With this rate and without competition, they could double or even triple their money in a few months. Very sound business plan from MtGox!
They don't care about their reputation and their customers anymore because they know very well they are going to phase out due to all the much better competitors. Their focus is all on short-term quick profits before their inevitable shutdown.