It looks like everything went okay with the server hamsters this morning as the servers are back up and running smoothly. In fact, it appears that all the servers are up right now. This is an oddity since usually there are at least one or two battlegroups that are down longer than the rest.
There is no patch 2.4.2 on the live servers right now, and the PTR (Public Test Realm) is still up and running for additional testing. Hopefully within the next week or two patch 2.4.2 will go live for us all.
WoW Insider will carry any updates on sever outages throughout the day. Enjoy your Tuesday!