Google responded, and today Vaidhyanathan offers paraphrased answers and additional analysis:
The agreements with and about publishers, libraries, and the registry were all non-exclusive, as is the habit and tradition of Google’s approach to competition in the Web business. The registry will be started with Google funds, but it will be an idependent non-profit that may deal with the Open Content Alliance and other services without restriction from Google. Generally, Google’s lawyers don’t see this service as presenting a “typical anti-trust” problem. There are so many segments to the book market in the world, including real bookstores, online stores such as Amazon.com, and used-book outlets that no one may set prices for books (even out-of-print books) effectively. There is always a competing source – including libraries themselves.
There’s additional coverage in Vaidhyanathan’s post.