Hmm, I guess it depends on what this will look like long-term, but I'd expect that regular uBO will be "upgraded" to this version when MV2 is deprecated in Chrome for good, possibly including the name change (if allowed by Google).
Edit: ah, looking at gorhill's comments it looks like this is not intended to be the MV3 version of uBO, but just one that has minimal permissions. Then I guess uBO will migrate in its own time.