Use Multiple Connections Between Tables (@PowerBITips)
The ALL() Function in DAX (@ExceleratorBI)
Responsive visualizations coming to Power BI
Power BI Desktop July Feature Summary
Power BI Service and Mobile June Feature Summary
BONUS ITEMS:
Data Privacy Settings In Power BI/Power Query, Part 4: Disabling Data Privacy Checks (@Technitrain)
Integrate Power BI into Your Application: Part 5 – Data Source Management (@Rad_Reza)
Over 150 of the Best Machine Learning, NLP, and Python Tutorials I’ve Found (@RobbieAllen)