This is too weird to even try to search for here, and unfortunately impossible for me to reproduce.
I've just heard that a customer, upon checking out via Google Checkout, was shown shipping information (on the G.C. checkout page) belonging to what turned out to be that of the previous customer.
I know it's bizarre, but is there any way Marketpress could have a bug like this? Has anyone seen anything like this before? Could it have anything to do with running WP Super Cache?
I've just upgraded to Marketpress 2.5.2.