This is not a done deal and the two organizations plan to take get feedback from their respective communities, starting with an in-person Q&A at the upcoming Node+JS Interactive conference, as well as online.
If this merger happens, then it’ll surely help both groups already sit underneath the umbrella of the Linux Foundation, which should make the transition relatively easy, assuming the community agrees. There is also some overlap between the two groups’ members, though probably less than you’d expect. While IBM is a platinum member of both, for example, Google is a platinum member of the Node.JS foundation but doesn’t sponsor the JS Foundation. Similarly, Samsung is a top-level sponsor of the JS Foundation but is nowhere to be found on the Node.JS Foundations’ site. It’s probably no surprise then, that one of the stated goals of the merger is also “streamlined member engagement.”