If I was starting from scratch I'd probably get a few Roku boxes since they're cheap and so simple to use and setup, but I already had a PS3 and that's what we used when Netflix first came to Canada a few years ago. I don't think Roku was even selling in Canada at the time.
We have 3 main viewing rooms - the home theatre (basement), living room, and master bedroom. I bought a second PS3 when the slim units went on sale, then I won a 3rd one at a fundraising raffle, so I had one for each room by the time we ditched satellite.
The living room and bedroom each have the 4GB XBox slim acting as a Windows Media Center extender for watching OTA TV. I got one on sale from Dell for $130 and bought the other off Kijiji. If Microsoft wasn't acting so greedy by requiring XBox Live Gold membership to use video apps I'd probably just use the XBox for Netflix/Hulu/etc. in those rooms and not have a PS3 there.
Adventures in Canadian cord cutting - »canadiancordcutting.blogspot.ca/