From the Microsoft article:
In early 2018, Microsoft announced the first machine translation system to translate sentences of news articles from Chinese to English with the same quality and accuracy as a person. Today, Microsoft Translator brings some of these research advances into production as it releases new translation systems for Chinese and German from and to English, increasing translation quality and expanding application scenarios.
Based on human evaluations using industry standard test sets, we are seeing up to 11% improvement in overall quality. The improvement is compared to our previous production API.
These improvements are a result of the research systems that achieved human parity translation on a commonly used set of news stories earlier this year, and which are now adapted to the production API. These include next generation neural net architectures and dual learning.
These improvements to translation quality for Chinese and German – from and to English – are available now on all Microsoft Translator apps, add-ins, Office, Translator for Bing, and through the Azure Cognitive Services Translator API for businesses and developers.
We will roll-out additional languages built on this advanced translation system starting early 2019.
The timescales for these improvements may seem long, but machine language translation isn't trivial. Notably, neither German or Chinese are 'easy' languages, so I'm inclined to think that the likes of French, Italian and Spanish won't be far behind.
We've already been seeing improvements in day to day operations in core Windows 10 UWP applications, we've been continuing to see security updates, and this Translator news is a great example of server side gains which are also seen on the phone. In this case, right back to Windows Phone 8.1, which also had a client for Microsoft Translate.