Read our latest: The year so far & 1.0 update.
After avidly following the github discussion, providing some input and reading the announcement blog post, the key statement for me was:
we don't want to spend time discussing and deciding on the best structure, designing a framework & creating documentation and guidelines so that new contributors can get up to speed
The focus is getting the job done, done in a timely manner, and done well. Productivity is frequently key when there is a clear end goal; when the end goal isn't to develop for development's sake, but to develop driven by creating a real product. There are a number of factors that can affect productivity and, as you can tell from the above quote, here's what the Ghost team were looking for:
I found the Ghost discussion and decision really interesting because we've been considering related points while open sourcing BladeRunnerJS (BRJS).
For example, we use a UI library called Presenter when we build trading applications. However, the need for a "semantically rich set of controls" may not be initially obvious and an additional new library dependency does increase the gradient of that learning curve.
Instead we've decided to make Knockout the default for our open source solution. Although this isn't as popular as Angular, Backbone or Ember it has a strong following, is very well documented, is actively developed and is probably the best MVVM framework out there. Presenter (built on top of Knockout) will instead be exposed as a tool for a more specific job (more details to come).
Here's a work-in-progress representation of what you get with BRJS:
A big thanks to the Ghost team for demonstrating that open sourcing is about much more than simply sharing code; it's about open discussion, sharing ideas and an opportunity for everybody involved to learn.