Forget about the speeches. The best way to predict what kind of "affordable housing" is planned by Forest City Ratner for Atlantic Yards is to look at the project agreements and bond filings. And it's not what the public was led to expect.
Gib Veconi's blog in Patch describes what little leverage the State has over delivering on the project's affordable housing commitment, and how Forest City is gaming the system to use scarce housing bonds to build studio and one-bedroom apartments for affluent tenants.
For the numbers behind the promises, see http://prospectheights.patch.com/blog_posts/atlantic-yards-affordable-housing-a-net-loss-for-brooklyn.