RIM calls their data/routing centers a NOC
I work for a managed services provider, and to us and most others in IT, the NOC monitors the health of the network, but RIM are Canadians.
I was surprised by initial reports that BES was unaffected, because every BES server must communicate with a NOC to exchange mail with the handsets. It is possible that RIM provides more back end services to BIS than BES, and that is why BIS is affected more. My recollection is that there were 2 or 3 NOCs that handle the entire world. It seems like a crazy architecture to me, being so centralized, but I assumed they had some really good backup/failover capability. I would have thought that RIM would have the ability to fail over to a backup NOC, but their architecture may make this difficult. Keep in mind that every handset is sending all data communication (web, email, BBM, IM, etc) through a NOC, The only exceptions are SMS (done by the voice network) and Internet access if you are using WiFi instead of the cellular network.
I did work for a credit card authorization provider and they ran everything on Tandem or Stratus systems (built with lots of internal redundancy), and if they lost an entire machine they could bring up another one very quickly. They had redundant X.25 links from multiple providers, and an X.25 switch (my part, sigh) with a lot of built in redundancy. Those guys were serious about eliminating single points of failure. If they are still around, perhaps they can get some consulting work with RIM.
Also, don't assume that when RIM says a "core switch" failed, they mean a Cisco 6509 or similar. They don't really tell partners anything about the internals of the NOC, but it wouldn't surprise me if a "core switch" is what we would call a server, or perhaps even a mainframe. Remember they are doing message switching, which is usually a store and forward setup like SMTP.mail servers.