I have Netflix and can stream on both systems. I used to have them wired to my router and the picture quality of Netflix streaming sucked. But now I'm using wifi on both and Netflix quality has improved 1000% on both systems. Even rented a movie in HD with that HD movie rental service on PS3, excellent quality over wifi.
Why would a wifi connection on both systems be faster than a wired connection?
What quality were the cables you had attaching the systems to your router?
I recently replaced the bargain basement cables on my brother in laws entertainment system and it made everything look and sound better... I

monoprice cables.