The new Map Viewer Beta is released! Recall from the October T3G webinar, that you access Map Viewer Beta from the App launcher ("the waffle") in the top right corner of your ArcGIS Online page (except Map Viewer). Also, when you start a new map, a message will give you an opportunity to use the Map Viewer Beta.
Here is the release blog post, Introducing the next generation of map making with Map Viewer Beta. You can try the quick-start tutorial, examine the product roadmap, and review the web map compatibility guide. If you aren't completely saturated, read the blogs just posted on the color ramps, dot density renderer, and pop-ups available in the new map viewer.
You can provide or research feedback, comments, questions and more in the ArcGIS Online Map Viewer Beta space on GeoNet.
Have fun! I hope you will share some of your educator perspectives on Map Viewer Beta below, as well!