Ordered one from Amazon the other day - hopefully I'll have it by the weekend.
I looked at the Linksys media centre extender as an alternative (PC World are doing them at £110), but my only PC is my laptop and I don't really want to have to fire it up everytime I want to listen to some music. It looks like a good idea if you've got a desktop PC you leave running as a file server, preferably over a hard-wired network, but doesn't really suit my needs.
With the WD player I can just leave it permanently connected to my AV system and hook up a spare hard disk with all my music and a few videos loaded onto it. I'm hoping that the sound quality will be decent enough - using lossless files and the DAC in my Sony amp there's no reason why it shouldn't. If the picture quality's good then I'll probably get a 2nd drive and transfer a few of my favourite DVD's onto it. It even outputs DD 5.1 audio off DVD files straight to the digital out.