Just got the disc to add Netflix streaming to the kids' Wii ... which means that it's no longer just the kids' Wii. I've got a loooooooooong "watch instantly" queue.
Activation was simple (insert disc, get activation code, go to computer and enter it).
I grabbed a flick at random to check it out. Fairly quick retrieval of the movie, decent video and audio, no observed skipping/halting. The controls using the Wii Remote don't seem very intuitive, but that may be because I've used a Wii Remote for a grand total of oh, five minutes or so before.
I've loved Netflix ever since we started with them a couple of years ago -- no more late fees, no time pressure to pick a movie at the store and get home, etc. -- but this jumps the service's utility up a full order of magnitude. Instant gratification direct to the tube. Cool.