That's right, NodeBB's widgets system is finally here. It will be officially released when 0.4.x hits in the next few weeks but if you're interested in trying it out in advanced, upgrade to NodeBB Edge.
A widgets-essentials plugin will be bundled by default with NodeBB, which contains the following basic widgets so far: 'HTML', 'Markdown', 'Recent Replies', 'Active Users', 'Moderators', 'Forum Stats', and 'Recent Posts'.
Here's how the Widget ACP looks like on the backend:
We also have a basic container system going, which we plan on expanding on after 0.4.x
If you're a developer, stay tuned - we'll write up a widget development guide shortly before 0.4.x launches.
Can't wait to see what widgets the community comes up with :)