Perhaps I should reformulate.

There are two strategies:

1) Finish new storage engine and release it as next update. It may take months. There will be no updates in between.

2) Fix backlog of issues that can be fixed without new engine and release them as they come. Work on new engine in parallel until it's ready for prime time. Then, merge two branches and finally release the combined version with all the fixes and the new engine.

I'll focus on #2 from now on.

Andrei