This is incorrect (possibly updated since you commented). The download link on the main atom.io site will download version 1.1. This is the first release that went through the BETA channel (i.e the beta channel was recently introduced as a way of trying out the latest version) to a stable release.
Although, the header on the blog post does still have "1.0" so it is confusing.
Although, the header on the blog post does still have "1.0" so it is confusing.