We're recently experiencing a big increase in errors and suspensions of the Microsoft translation memory.
rakkaus log random stats for August, September and October (not reliable): "Unknown error" 92, 141, 370; service suspended 8, 17, 203. It happens several times per day since October 6.
I don't know if we're using a key (the monthly character limit for free accounts is only 2 millions https://datamarket.azure.com/dataset/1899a118-d202-492c-aa16-ba21c33c06cb ) but I doubt that can be the problem as August had about three times more translations than September or October.
There don't seem to be big news about the service except a new commercial brother service three months ago https://blogs.msdn.com/b/translation/archive/2012/07/11/announcing-the-microsoft-translator-hub-for-commercial-use.aspx and a capacity expansion last year https://blogs.msdn.com/b/translation/archive/2011/10/18/top-sites-going-global-with-translator-api.aspx