This is a very neat, very tiny streaming box with a surprising amount of connectivity for its size (hdmi, composite video, usb, micro sd card slot, wired and wireless networking, rf and ir). The device seems to be well made, and comes with power and composite video cables - ethernet and hdmi cables are not included. I have two of these boxes connected to my wired network via Devolo homeplugs, which are a good way to get a wired network point behind a tv set, and they work well.
Setting up is very easy, and on-screen prompts walk you through it. I was slightly puzzled at one point, after letting the box download the latest software, when all I could get on the tv screen were bouncing purple Roku letters. I thought maybe things had locked up, as pressing all the buttons on the remote made no difference (must be the modern equivalent of banging something to make it work!) but I eventually deduced that the bouncy purple letters are displayed while the box is installing its updates, so if your system sits on these for a while, don't worry, it gets there eventually.
Once installed and updated, you can add various content channels either via the website or directly on the box, and in addition to the vetted and approved options in Roku's channel store, there are also private channels, which can be found by googling if you're interested. Roku divides its channels geographically, so UK content is at present quite limited. Having said that, there are more channels than I expected, including movie channels devoted to eg, Anime, old Westerns, old Hollywood films and the like. There are also various news, weather, tech, and other assorted sites, and a number of games. However for most people the main reason to get this box at time of writing is for Netflix, the shining star in the collection, but Lovefilm is due to arrive imminently, and Roku are keen to get 'big local content deals', so that might (or might not) mean the likes of iPlayer and 4oD one day. On their forum Roku state that "We will be adding channels each week in the UK and Ireland as we do in the US. Many of the private channels in the US will likely show up in the UK". Note that not all channels are free; Netflix requires a subscription, as will Lovefilm when it arrives.
A tip whilst registering if you have a smartphone, it's worth getting the free Roku app as this makes entering text for netflix logins etc much easier than using the onscreen keyboard with the Roku remote.
Although the box sets itself up automatically, you can change things like display resolution (720 or 1080p etc) and audio (stereo or 5.1) in the settings menu.
Very generously for such a small device, this version of the Roku box not only has rf functionality (supplied remote is bluetooth, so no line of sight needed) but also ir, which means it is compatible with all-in-one remotes including eg, the Harmony One. Note that Harmony list Roku under DVD devices.
The box has adaptive bitrate streaming, which means it adjusts the amount of data it is pulling in to match your connection speed and keep the stream flowing without buffering as far as it possibly can. This works if your linespeed goes up as well as down: if your connection improves, it will improve the picture, and vice versa. With a reasonable internet connection streaming works very well, and begins within seconds of choosing a program, so no waiting for films or tv to download.
With Netflix you can additionally choose the video quality that programs are sent in if you wish at the Netflix website, and the options range from "Good Quality" at 0.3GB per hour up to "Best Quality" at 1GB per hour or up to 2.3GB per hour for HD. This may be helpful if you have a download cap. Note that Netflix's current definition of HD starts at 720p. The quality of the tv programs marked as HD is variable; some are excellent, some look a little soft to me, compared to even SD broadcasts from some of the higher quality UK tv channels (viewing on a couple of very good panasonic hd tvs, over a stable 7.5MB connection, so should be about as good as it gets), but considering it's a streaming picture, overall it's really very good. One could wish for a little more definition here and there, but it's nowhere near being a deal breaker.
The Netflix user interface on the Roku is particularly nice: it's clearly been designed with a 'lean back' experience in mind (ie, sat back on the sofa rather than 'lean forward' as with a computer) and the icons/tiles for the programs are easy to see from a distance, and the synopsis text is easy to read. This is true even on a small screen, eg I have a 24 inch screen in the bedroom, and the display is very usable from the other side of the room. Much more readable, for instance, than the Lovefilm interface on the same screen via a Sony Blu-ray player.
One point to bear in mind: streaming video in the sort of quantity that the Roku/Netflix combination encourages causes your data usage to rocket. If you have a capped or limited broadband package, it might be an idea to keep an eye on your usage until you get a sense of what it's typically going to be if you're subject to fees or throttling/slowdown etc for exceeding your package.
Overall, despite the relative lack of channels at present, in my opinion this is a five star streamer - very small, very well-designed, well-made, very easy to use, and effective. Whether it's worth the money for Netflix alone, if the other channels don't interest you, will depend on how much you intend to watch; for me, it's worth it for the instant ease of use, (no messing around connecting the laptop to the tv), the quality of the streaming, the readable display, and for future channels such as Lovefilm.
10/02/2012 Update: BBC iPlayer is now available, with another very good and user-friendly interface, including a 'Favourites' feature for easily keeping up to date with your favourite programs.
26/04/2012 Update: Just a comment on how the content is progressing. The number of channels is steadily increasing, with new ones being added each week as promised: the tally is already over a hundred. Most of the new channels at the moment seem to be making their way over from the US. As far as the UK catch-up tv services are concerned, there may be a little while to wait, but Roku sound encouragingly pro-active about building the content according to an interview with Pocket-lint last month: "Roku...is talking to all the relevant catch-up services in the UK to bring them to the new Roku box...'The BBC iPlayer is the only catch up service on there at the moment. That will change. We are talking to all the guys you would expect us to talk to', [said] Clive Hudson, head of Roku in Europe".
18/07/2012 Update: The newly launched internet tv service from Sky, called Now TV, will be added "soon" according to Roku's blog. The service offers films on a pay-per-view or monthly subscription basis, with other content such as sport and programmes from Sky Living and Sky Atlantic to follow.
28/11/2012 Update: Sky's Now TV service has arrived. The interface is quite clunky; hopefully it's a work in progres and Sky will make it slicker over time. Small tip: at time of writing you can get 30 days free trial and then, if you wish, up to three months subscription at 9 pounds instead of 15 per month, no contract, cancel at any time. You can also get ten pounds cashback via Topcashback.