The preview of CTP 1.1 of SQL Server vNext, the latest version of SQLServer, contains important new features and enhancements for Analysis Services Tabular:
Connecting to new data sources as currently offered by Power BI: multiple file types, databases, Azure sources and other online services, Big Data systems, Facebook, etc.
Possibility of transforming data directly into the tabular model: dividing columns, hiding columns, changing data types, etc. using a query editor in the style of Power Query and PowerBI.
Custom drill down in Microsoft Excel: allows you to customize the detail of a measure’s data in an aggregate report. For instance, when end users see the total sales per region and per month, they can see the detail of the associated order.
These enhancements, along with DAX’s improvements and security enhancements, will make tabular models the most recommended in most scenarios. You can see further details in this Microsoft blog entry.