Moshe Vardi wrote an editoral about open access in the CACM in 2009. And others have followed up why it can’t, won’t or shouldn’t happen. I myself am skeptical that the organization can let go of the Digital Library cash cow; if even a quarter of the roughly 80,000 ACM members pay the additional $99US per year for access or take the professional membership I figure it would generate about $1.9M per year. Yet Usenix, an organization a magnitude smaller, manages to make its proceedings and papers available. This open access is good for the field.
Professor and cryptographer Matt Blaze weighs in at his blog with Copywrongs.