Sunday Dec 29th 2013 all day long I-90 all the way across new york state and along I-79 from Pittsburgh to Erie PA was unable to connect to the routing server. I would try every 15-20 minutes. Today (Jan 2nd 2014) was the first time I tried Waze again, my daily commute to work, I-95 around Boston area was unable to connect to the routing server with several attempts on the way in, 8-9 AM EST. I'm able to connect now, while in the office at at work. In both cases I was able to use internet on the phone and download maps while traveling, notifications were working, but routing was not working at all.
Too much traffic? High load times? (routing traffic, not car traffic!!!) I would have expected Sunday the 29th to not be a high load situation. Perhaps AT&T Wireless is blocking the routing server?