All future papers published under this model will be made available through these repositories at the time of publication.
ACS [AuthorChoice] articles are fully open access in the sense that the licence allows users - for non-commercial research and education purposes - to "access, download, copy, display and redistribute articles as well as adapt, translate text and data mine the content...."
The open access movement:
Putting peer-reviewed scientific and scholarly literature
on the internet. Making it available free of charge and
free of most copyright and licensing restrictions.
Removing the barriers to serious research.
I recommend the OA tracking project (OATP) as the best way to stay on top of new OA developments. You can read the OATP feed on a blog-like web page or subscribe to it by RSS, email, or Twitter. You can also help build the feed by tagging new developments you encounter.