Though the Xbox 360 version of Netflix does not require a disc to use, the PS3 version does, which actually pissed a lot of people off due to the inconvenience.
But now Netflix will be an instant streaming service just like the Xbox Live version, and it will be available by the end of October.
“Before our next [earnings] call in October, we expect to be launching a major new version of our Sony PS3 user interface which doesn’t require a disc, and is dynamically updated continuously with the latest Netflix UI improvements.”