mtgox/coinbase spread is also growing over the last couple weeks, now ~$12 difference.
this indicates
significant problems beyond some simple delays in withdraw/deposit times at mtgox. i do not know exactly what problems, but we will find out eventually.
i have not used mtgox recently therefore unaware of all the details that are public. but a quick glance at their website led me to the following statement that strikes me as somewhat fishy:
For example it currently takes up to 10 days to process a deposit because our bank, upon receiving deposits, notifies us of the deposit but holds them for 7~10 days before transferring them to our account. This has always been the case, and we were still crediting customer accounts before receiving the funds ourselves, but some cases in which the bank subsequently rejected the deposits meant that we incurred significant losses. The risk is now too high for us to credit accounts prematurely. We are in the process of forming relationships with new partners, banks, and taking other steps -- hopefully we will not only be back where we were before we encountered these issues , but much further ahead.