Important: This post was written and published in 2020, and the content below may no longer represent the current capabilities of Power BI. Please consider this post to be more of an historical record and less of a technical resource. All content on this site is the personal output of the author and not an official resource from Microsoft.
In case you didn’t have any plans for the weekend, the Power Query team has released a treasure trove of new documentation for dataflows in Power BI and Power Apps.
You can find the new docs here: https://docs.microsoft.com/en-us/power-query/dataflows/overview-dataflows-across-power-platform-dynamics-365
There are over 20 articles in this new resource, and the content they contain answers many of the questions I hear most frequently. For some reason WordPress isn’t letting me upload the screen shot I took of the content outline, so instead here is a picture of me when I first learned about this new content:
Please check out this new information, and please submit feedback to the documentation team using the feedback form on each page. When you let the docs team know what you like, what you don’t like, or what is missing, they read every comment!
 Me in my avatar as a photogenic young woman.