Therefore we may surmise that Minecraft: Education Edition will be a subscription-based licensing model. Kind of a bummer but I get it, teachers are pretty resource-intensive to support, and the value comes from building up the community and resource/lesson/world sharing, which is an ongoing cost.
The school where I teach had literally just last week decided to take the plunge and purchase some MinecraftEDU licenses. I'm just glad we will still have them in perpetuity (whatever that is good for in the constantly changing world of software!) along with the full retail copies that come along with it.
Really I hope this will deliver on the promise of Minecraft in the schools. MinecraftEDU was a fine first step but it is clear that it will benefit from having the full resources of Microsoft behind it. Currently it is still a bit of a "throw the software at the community and hope something good comes of it" approach, which is very hit or miss. Teachers are making a lot of great lessons and activities using Minecraft, but many of them are very localized to exactly what that specific teacher is trying to accomplish and are difficult to generalize to "all 4th grade teachers can use this". I would liken it to what Scratch offered for coding in the classroom ("here's the toolset, have fun!"), as opposed to what Code.org brought to the table with more of a complete packaged lesson plan and hand-held guided experience through a coding activity using Scratch.