I have a samsung blu-ray player (BD-P3600) that has this feature built in.  From what I can gather it has the same chip set for Netflix stearming as the Roku box. 

 It works very well.  It was a snap to set up and it takes maybe 1 minute to buffer a movie (even one in HD).  It automatically selects video quality based on available internet connection speed.  Most recordings are DVDish quality which is very watchable to me.  The HD recordings are nice but imho do not compare to broadcast quality.  But for shows or flicks that I dont need to see in almighty 1080P it works great.

One caveat is that it only supplies stereo sound even HD videos.  I have heard that Netflix is working on this.