We have both and I much prefer the Roku. It's faster, more user friendly and just all around better. That said, we do use the Blu-ray a lot so I'm glad we have it.
I'm trying to choose between a roku 466r streaming movie player and an LG bp350 bluray player that can also stream movies. The lg is $40 cheaper. I have a Netflix account. Is there any advantage the roku has that I'm missing?