how does bitinstant fund your mt gox account?

[WishIStartedSooner]

You send your money to bitinstant through zipzap or some other intermediary that they have a deal setup with. I get that.

What I don't get is what is it that bitinstant does that allows them to fund your mt. gox right away? Do they have come kind of deal worked out with mt. gox? I guess I just dont understand why I can't directly fund my own mt gox account.

[hamdi]

they keep reserves on their mtgox-acct.
as soon as they got your zipzap in their bank, they pump your mtgox-acct. from their mtgox-acct.