When Netflix landed on the Xbox 360, it radically changed the way I used the service. I barely paid attention to my physical disc queue and instead instantly streamed Excalibur over and over until I started talking all nutty like Merlin.
PlayStation 3 owners will now similarly be able to ruin their lives as Netflix is going to add the service to Sony's big black box before the year is up. It looks like you'll need to get a free disc sent to you through Netflix to get things started — whereas Xbox users only have to download an app for the service — though it's unclear whether it's just a simple one-time install or a disc you have to insert whenever you watch movies.
Other than that you just need a Netflix account, even one as cheap as $9. The PlayStation's online network is free, as opposed to Microsoft's premium Xbox Live Gold service, which is required if you want to get your Netflix stream on.