Yes, after an automatic Smarthub update this morning normal service has resumed.
Quite a long outage! Samsung don't have a service status page so it seems the only way you can see if there's a problem is to look for angry/upset customers on Twitter and forums!
We used a Google Chromecast to get our TV online during Samsung's problems.
Perhaps buying an expensive Smart TV wasn't such a good idea when a £20 Chromecast keeps working!