This looks like Obsidian's first move away from using some dialect of markdown? The .canvas files appear to be human readable json, but certainly not as readable as markdown. I'm excited to try this out, but I hope this isn't a trend towards using proprietary formats.
We considered many options to use Markdown but came to the conclusion that Canvas is not something that can fit into a readable Markdown file. Either the Markdown file would so messy that it becomes pointless (i.e. you would never open it in Typora to edit), or it would severely limit the power of Canvas.
After much internal debate we chose the JSON format. We stay committed to keep it as open and easy to work with as possible. Plugin developers are already parsing and modifying the JSON file to programmatically change a Canvas view, and I think that's a fantastic start!
Now that you crossed that line, I hope the next "custom format" will be a "real" outliner. You are surely familiar with outliners ;-) It is about full block-level support really, and all what that allows (API, backlinks, query, aliases...)
Opportunity cost. I wrote on your forums about the decioson of using plain markdown. Consider other formats to stop bloating(yaml and dataview variables) markdown files. Now you have bloated md files and another format. Now i am saying you will add sqlite after one or two years. Waiting for extra file formats making existing files ugly.
Also obsidian needs multi user vaults. Start to think what extra file format needed for this.
The .canvas files are a JSON-based file format that we open-sourced under MIT license. Just like everything else in Obsidian, it's still all local files on your device.
If I understand it correctly, the use case is to link existing MD notes visually. That's a different way of looking at the data than the two-way backlink approach that was the foundation of Obsidian (and other personal wiki tools).
I'm interested in this, as I currently use a combination of Obsidian + SimpleMind, but currently SimpleMind has more features (full fledged mindmapping app), and I like having two separate spaces to sketch out ideas.
I also use both, Simplemind is a fantastic mind mapping app.
For smaller scale mindmapping though, I am finding Canvas very usable already for such an early release. The ability to easily link or embed to markdown files (or create new ones) is really nice, and I like having all my work in a common area. Community created plugins will also dramatically expand the app.
There will always be advantages for the dedicated apps as well, but this is going to be a great option for many.
