I just picked up the Roku Netflix Player last week, and boy have I already become addicted to it. The setup is incredibly simple...Just power it on, connect your A/V cables (I used HDMI), connect to your wired or wireless network, register the device on the Netflix website, and you're done. Took me literally 5 minutes to set the whole thing up...piece of cake for anyone.
When you go to the "home" screen you are presented with your "watch instantly" queue, and just like everything else with the player it is brain dead simple to navigate through the queue and select what you want to play. Once you make your selection, it does take a few seconds for the player to start downloading/buffering the content before playing it on your screen, and the player also determines the "quality" level of the stream depending on how fast your internet connection happens to be at the time. If you are like me and always demand the highest quality, then there is a back door way of forcing the unit to stream at a set quality level - you can find out how by visiting the Roku Netflix Player link on Wigix. Sadly there is no way for you to search for new titles to add to your queue from the player itself; you must go back to the website to do this. However, you can remove an item from your queue as well as rate it from the player.
Probably the main drawback to the player is its lack of a hard disk, so the player is only able to buffer a small amount of the video if your internet connection takes a hit. I suspect that the reason for a lack of a hard disk is mainly due to the paranoia that the Hollywood studios have about content piracy. However, in the 10 or so hours I've used the player so far I've only experienced one instance where playback stopped, and even then it only lasted a few seconds.
I was also pleasantly surprised by the quality of the video stream produced...I think it was pretty comparable to a standard DVD player. And the player is also capable of streaming HD content, and Roku has stated that HD content will be available by the end of this year...this is great news! Unfortunately, though, both the current content as well as the HD content will not support any multi-channel audio formats. Again, this appears not to be a limitation of the device but by the studios' refusal to release those formats with their content.
How does the Roku compare with other video streaming products? Well, I'm not really an expert here, but there are two others that I had considerecd. The first was Apple TV, which appears to be getting better and better with each release. And the unit does come with a built-in hard drive and so it shouldn't be as prone to any hiccups due to connectivity issues. However, with the Apple TV you need to purchase any of the content you want to watch. Vudu is another competitor, and their big advantage is that they have quite a bit of HD content available. However, similar to the Apple product you must purchase or rent all content, and I don't think Vudu is getting many subscribers and so I have a feeling they may end up going out of business.
Overall I'm as please as can be with the Roku, and I really think this is the future of where video subscription is headed. And I'm sure Netflix would love nothing better than to not have to physically ship all those DVD titles to their subscribers, which is why they are pushing really hard on "watch instantly" and working with various hardware providers to support it.
UPDATE: Roku launched support for HD content during the holidays. The amount of HD content is pretty minimal right now (mostly TV shows) but will grow rapidly over time. Netflix is in the process of re-encoding all their Watch Instantly video streams, and as part of this effort you'll see more HD content availability.