The rogue DNS servers are reporting MIT's main web server IP for all DNS name queries (other than for the main web server's name) to people that are off campus. So, to someone outside MIT (depending on DNS caching), it looks like everything is down.
Also, ASP/SAAS companies in the .edu space often use a DNS name that is part of the school's domain in their model.
I don't know much about this stuff but different server or not - if the domain is hijacked then everything is broken, no?
E.G. if they had blackboard (course docs, homework, etc.) on blackboard.mit.edu then that would be hosed right now, wouldn't it?
If you're on the internal network, you're most likely using an internal DNS server which would not care that the registrar claims some other DNS server is now authoritative.
I suppose it could be a problem if you're not on campus; or if any third-party services are not using their own domains (e.g. mit.blackboard.com)
Now, all the other crap-- course scheduling, grades, classwork --is likely not living on the same server. Many of these things aren't even hosted inside the school's network but provided by some outside company.