Bitstamp has simply taken the role of Dwolla, Liberty Reserve and OKPay for Gox traders at the moment. Without Gox Bitstamp would collapse within a few hours.
This statement seems to make no sense. Gox traders using Dwolla would deposit USD to Dwolla, transfer the USD to Gox then buy bitcoins....how can this be done via Bitstamp?
You'd have to be very brave or a fool to deposit USD to bitstamp, buy bitcoins, transfer them to Gox, sell them on Gox and pray for a withdrawal (hence the 10% premium as no one wants to do it).
And the reverse doesn't make much sense either. If I deposit USD at Gox, then buy bitcoins then transfer them to Bitstamp and sell them for a 10% haircut, then withdraw USD...that is not something I'd want to be doing on a regular basis.
I was using Gox exclusively, now I'm using Bitstamp exclusively...why would I have any reason to go back to Gox? I have already reconfigured my systems to also work with the bitstamp API.
How would Bitstamp collapse within hours? Provided they are not running a factional reserve then their orders will balance.