The folks at Neowin managed to get hold of a document which sheds some light on the updates pushed out to beta testers for the month of January. Rather than introducing new features, the updates focus on improving the existing features by adding some new functionality to them. 

 

Here's a list of changes:

• Forecasting Functions
  
• Time Grouping for Model Based Pivot Tables
  
• PowerView over an OLAP connection
  
• Data model PivotTable Automatic Relationships Detection
  
• BI in Excel - BI features discoverability
  
• Updated Backstage UI
  
• Rename Tables, Columns and Measures in Power Pivot and Adjustments of the PivotTables
  
• Data Cards
  
• Skype for Business

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