The REST API has landed in the master branch! Max Rice has been going above and beyond in the past month to get the REST API implementation ready for merge into WooCommerce core. This morning, I had the awesome job to merge it to the master branch and start testing it extensively.
This was the last big issue left on our tracker before we could release the first beta of WooCommerce 2.1. You can imagine that I’m really happy that Max pulled this off, well ahead of our beta 1 schedule. There are a couple things to discuss (soon to be posted as issues on our tracker in GitHub) for the API still, but these are not required for the WooCommerce 2.1 release. We can add them as soon as they are done, or they will be released in with WooCommerce 2.2.
For now, we can all start testing the API so obvious issues can be fixed before we release the first beta. You can find a list of all available API endpoints in the original pull request on GitHub. We still need to finish the documentation before release 1 date, but for now this is all we can offer for initial testing of the REST API.