The official blog says it:
We’re excited to announce today that Netflix and Sony have partnered to bring you thousands of movies and TV episodes streamed instantly from Netflix to your TV via your PS3 system at no extra charge. When the application launches next month, you’ll be able to access and watch thousands of Netflix choices directly through the XMB. We think that the nearly nine million PS3 enthusiasts and 11.1 million Netflix members in the U.S. will make quite a match.
Key words here are *no extra charge*
EDIT: Wanna find out the moment it's released? Go here: www.netflix.com/ps3