hey! I am not familiar with the exact specs of the bd570 vs. bd-590, but l am more than happy with the unit! Netflix works flawlessly, as well as Pandora and Picasa web albums. The 590 was a bit expensive, but the built in harddrive for media storage is awesome. It can hold all forms of music, pictures, movies, etc. The load up time was quick, and blue ray playback was sweet! Sound and colors reproduced wonderfully.
Streaming of Netflix works great, and LG has set it up with a great interface with setting up your movie cue and scrolling thru the movies available. Pandora....awesome, period. All work, and sound great thru your home theater system, especially Pandora. I didn't notice any jitters in Netflix, and will agree, probably better than watching on a computer.
Go ahead, bite the bullet, and buy one. Don't know your finances, but I certainly am glad with the ability to store media right on the built in hard drive, and would recommend going that route..upload litterally hundreds of cd's and nver have to change disks, etc...
Let me know how you make out with your purchase!