I recently picked up Roku2 at Costco. I figured that we can try using it for streaming some media from the internet and the PC. My initial impressions were not very good because of the defective remote. The remote would lock up about twice a day and I had to remove and replace the batteries and that was very annoying. Other than that device was OK but it did not support many formats. After talking to the Roku customer support person I returned device to Costco and got WD TV Live which a lot of people liked. After using Roku2 and WD TV for a week each I formed my opinion.
In streaming from the internet Roku wins hands down. It has many more channels, some even very good. If you only want to use Netflix and Hulu, WD TV is OK. If you want more choices Roku2 is your box! It has bunch of educational channels like Khan Academy and MIT Open Courseware.
If you want to stream variety of formats locally WD TV could be a better choice if you do not want to transcode. Since I occasionally had to transcode video for iPod, I already had Handbrake and has no trouble transcoding for Roku. Roku only supports H264 and VC1 codecs and only few containers, while WD TV supports a large selection of codecs and containers.
To stream locally with WD TV you can use DLNA server or just use windows sharing. Windows sharing is dangerous to use over wifi since my network is not secured. All DLNA servers that I used are huge and clunky. At the end I used ps3mediaserver which after running overnight grew to 1GB in size. There is NO REASON why a glorified web server should be that large.
To stream to Roku, one also has several choices. I tried two - Rocksbox and MyMedia. Rocksbox is pretty good and works well. It costs $15 after a month trial period. It works together with the monogoose webserver or any other webserver that you can configure. The monogoose server is light, small and fast. It is very easy to configure.
MyMedia server has its own server solution written in Python and the source of the Roku app is included. I liked that approach since I could add features and fix any problems, not that it had any. At the end I went with MyMedia and it works very well. Memory footprint starts under 10MB and grows to around 15MB after running for a while. The server is responsive and supports multiple Roku units.
In the user interface department Roku2 wins with the large margin. User interface is fast, responsive and intuitive. WD TV is very far behind. You can tell that this product was done by the company with no experience in user interfaces. UI is sluggish, progress indicators are absent in the few notable places. You think that box is hung but after a few long seconds it comes alive and does its thing. The WD TV is never actually hung but I thought several times that it did.
WiFi performance is much better on Roku2. When away from the router WD TV had trouble with the streaming and video would often freeze. Roku never had any problems.
So over all my preference is Roku2. The only area that falls short is a media format support. Given fast computer and handbrake it is not a huge problem. On my quad core AMD Phenom PC 1 hour SD movie is transcoded in about 6-7 minutes. This machine is about half speed of modern i5 or i7 machine.
WD TV power consumption about twice that of Roku2. Not that it matters much since both boxes consume under 10W. Roku2 consumes under 3W when running and less than 2W when screen saver is running. KillaWatt could not detect any energy being used by Roku2.
The only area WD TV box is better than Roku2 is the media format support. If you are not willing to transcode your media but instead willing to live with clunky and slow interface, WD TV is your box. If you want many free and good internet channels, willing to transcode and like good interface experience, go with Roku2.
Costo bundle of Roku2 XS contains 2 months of Hulu and a HDMI cable. Given that the price of the bundle is lower than just a Roku box elsewhere, it is a very good deal. Do not forget a complete Angry Birds game which comes with this Roku box.
WD TV Live went back to the store and I bought a new Roku2 unit at Costco. This unit does not have the problem with the locking up remote and I am very happy with it.