So it itself consumes ~5 watts, does this include the hard drive and routers required to store and transmit the data, or solely the device itself?
It's a packaged sheevaplug http://www.marvell.com/products/embedded_processors/develope...
You can do the same thing using fuppes, an updated version of uShare. Fuppes also supports transcoding, uses a sqlite backend and can rescan watch folders to rebuild the database pretty quickly (either from cli or web interface, without restarting). I use it to stream to an xbox360 and it works perfectly. Haven't tried transcoding though since all my video is compatible.