"Rigel" appears to be the codename of Netflix for PS3 version 2.0, according to this slideshow purportedly by "David Ronca", the "Manager, Encoding Tools" for Netflix.
The slideshow outlines the development history of the Netflix client. The info's a little dense without the accompanying slide notes, but I've taken a stab at assembling a timeline. In short:
- The first streaming client was an IE-only ActiveX plugin that hosted a Windows Media Player instance to which it delegated the actual playing of the video
- There was then an SDK (called CE1) on top of which a client for the Xbox was built, as well as the first Roku-based clients
- The ActiveX client was later replaced with a Silverlight client for better cross-platform capabilities
- This lead to a second version of the SDK for console boxes (CE2), which offered better capabilities and a Flash-based UI
- The first PS3 client, named "Vega", was based on the PS3's innate blue-ray reading technology
- The first Wii client was named "Link". It struggled with profile bloat introduced by DRM handling
- CE3 was released
- The first iOS client was called "Nato". It was built in a few weeks between Apple inviting them to be part of the iPad launch and the actual iPad launch. It uses HTTP Live Streaming, which was a totally new model for Netflix. It was based on Vega
- An upgrade to Vega rolled out this HTTP Live Streaming concept to the PS3
- Vega was replaced with Rigel, which is a native PS3 app (for better performance)
- Link was replaced with Kirby, which is again a native Wii app
- The latest SDK is CE3 version 2, which supports a standard called "DASH". As of May 2014, CE4 is under development.
I don't know if that helps, but I found it interesting at least :)