The CC to Video Game argument is a terrible comparison. First off, does anyone here even have intimate knowledge with what information is passed on each transaction and how many servers are hit by each transaction worldwide? CC transactions are split up by acquiring bank and card issuing bank so that we are now talking about dozens of banks. They are also done in 2 parts, the "real time part" is just an authorization of the code as well as the amount of money that is put on hold. Then later that night, the actual transaction is processed.
You're wrong about both the network and the authorization steps, although not entirely in the last case. Any given transaction originates at a particular merchant, hits the acquiring bank's processor, then the Visa or Mastercard backbone, then Visa?MC's mainframes, then the issuing bank's processor, then takes the same trip back. On the way it updates at least four massive databases that handle about a trillion transactions per day. In the U.S. the vast majority of the processing is handled by four non-bank entities: Visa, Mastercard, First Data, Total Systems; and by about ten major banks such as Citi.
In terms of auth, the old auth + batch capture step has largely been replaced by one-step auth/capture for higher volume merchants. They use batch reconcilliation at regular periods.
In any case, all you've argued is that there are even more individual components to each transaction, hitting more databases than I described. Even if I stipulate that you are correct, that just adds complexity and failure points.
You might think it's a terrible comparison. I don't. In both cases you have all the same basic components of an ACID transaction: client, message, transport, protocol, DBMS, storage. What you can argue is that the individual messages are more complex, and the database state more complex, for WoW than for a banking system. I already conceded that with a caveat for trading systems.
The end goal, however, is the same: a high volume stream of ACID updates to a large database over a public/private network. If WoW is more complex, then the banking system serves a much higher volume of transactions.
Note that I am not criticising the game for bugs, or whatever other errors it manifests. I've built both credit card systems and gaming software, and I have a lot of respect for teams who do either. All I am saying is that at certain levels of volume and revenue generating potential, massive investment in availability is required. I doubt that Blizzard has made that investment, but I don't doubt they are working on it.
