As was announced on the forums on 4/30, Salesforce is setting up additional logical servers (NA1 will be split out into NA1, NA2, NA3 and NA4).
There seems to be work being done at this moment. All of my Developer Edition accounts now route to NA2. NA2 is not up and running yet, but my Developer Edition logins are being routed that way. I am sure there will be an announcement from Salesforce soon as to what’s taken place.
My client’s accounts still route to their original servers (NA1, EMEA, etc.), so Salesforce seems to be taking it safe on who they move to that server today.
It would have been nice to have had some warning that these accounts would be routed to NA2 today. It’s been somewhat of a disruption this evening. Not a big deal, but it’s nice to know if an account is going down. Even if it’s only a free Developer Edition account.