My takeaway from the announcement is the importance of installing all the 123D apps now (and archiving the installers where possible) until they decide where Make, etc. will end up.
From their knowledgebase:
Can I still use the apps?
If you have a version of the app on your phone, tablet or desktop you will still be able to use it, but over time the app may not continue to work in the same way. Some will have limited functionality and some will continue to work without problems.
We will no longer be developing or supporting the 123D products after March 31, 2017.
Are there other Autodesk apps I should look at?
Don’t worry; we have great products for you to transition to. Initially, we suggest exploring Tinkercad, Autodesk Fusion 360, and Autodesk Remake.
In the coming weeks/months you will receive additional information about this transition. Here are links to some product information and training if you want to start exploring today.
Autodesk Fusion 360: http://www.autodesk.com/products/fusion-360/overview
Autodesk Remake: https://remake.autodesk.com/about