I was on holiday for the last couple of weeks so I had only a limited coverage of what happened since the beginning of the month 
Why such an emphasis on my end? Well, because custom rules on Work Items involved fiddling with xml files and command line tools or using the Process Template Editor in Visual Studio and a UI that is a bit tough.
It is something that any TFS administrator does on a regular basis though. Now rules in VSTS can now be defined in a web UI with a consistent experience and multiple sets of conditions and actions can be defined easily in the same page.
Also, this makes involving team managers in the definition of these rules extremely easy, as there is no Visual Studio, XML, command line involved anymore.