Dev4Press has a summary of the current state of Gutenberg (version 2.4).
Antonio Villegas shows how you can create your first Gutenberg block. He briefly covers the edit and save methods in his example.
Karim Marucchi explains what Gutenberg might mean for large, complex websites. In the end, Karim says the inclusion of Gutenberg into WordPress isn't going to break existing websites. But a “solid upgrade plan with risk-mitigation assessment and thorough pre-deployment testing” will be necessary.
The Gutenberg Plugin Compatibility Database project has been started to identify whether the 54K+ plugins at WordPress.org are compatible with Gutenberg or not. It's a crowdsourced tool so they are asking for “lots and lots” of volunteer time for testing.
Brian Gardner shows how to add theme colors to the Gutenberg Editor. Brian also notes he will be exploring Gutenberg's impact on the community of developers and customers who build sites with Genesis.
Interesting to see how some WordPress agencies and companies are preparing for Gutenberg. WebDevStudios, for example, has assigned two internal leads just for Gutenberg and creating a framework that will standardize a number of content blocks.
If you've wondered about the Gutenberg Editor's potential impact on performance, check out the results of the tests Greg Schoppe did. Greg wrote a benchmarking plugin and then generated two identical pages: one with Gutenberg activated, and the other with it disabled. While some parts of Gutenberg were faster, the overall rendering time for a simple text-only post increased.
No doubt Gutenberg still has to be optimized and will continue to be even after it's launched, but these tests show how important that work will be.