"All your favourite personal and Internet media on your HDTV" it says on the box.
In fact it's a 1TB Internet enabled NAS (network attached storage) box. It connects to the TV via HDMI for HD and component or composite cable for SD and to the home Ethernet network. Then you can transfer your content (photos, video, music or whatever) from the various computers round the house and view them on the TV or from other computers connected to the home network.
The system is localised - you can set your local language, time and place, daylight saving etc. But there is no way of changing the onscreen temperature to Centigrade from Farenheit.
The installation in Windows XP involves downloading a piece of softwre just so you can see the box on your computer. While the manual (online only, not in the box) states that this is possible, you are asked for a password. The default password is on page 74 of the 168 page online manual, which of course I only looked at afterwards.
My Linux (Ubuntu) computer found the box with no problem. I couldn't figure out how to see it with an Android phone connected to the home wifi network.
While the Internet service could be a useful feature, it's by no means a fully fledged access. In fact, you can only connect to a handful of selected sites, like Facebook and Flikr.
Quite a few video formats I tried to use were incompatible.
I was pleasantly surprised by the viewing quality of streaming video on Youtube. Much better than on my computer.
OverallI don't expect it to sell well here in France, where the internet connected homes are based on high powered boxes that combine modem, router, PVR and other functions. The forthcoming Freebox V6 is a much better solution, with full Internet access and a much better user interface. The only advantage of the WD is the 1 TB of storage capacity, compared to 250 GB on the Freebox. But then, you can always hang extra hard drives onto it.
The WD box makes a good complement to the Slingbox I've recently had on test, although some functions overlap (streaming round the home). Merging the two would be good.