I considered a SoundBridge M1000/M1001 and the SqueezeBox 3 for quite awhile, weighing both heavily. I ultimately decided on the Roku because of the cost and because of native Apple Lossless (ALAC) support. Native ALAC is huge for me.
I received my Roku yesterday, not intending to have "time" to set it up and play around with it until sometime during the weekend. I decided to at least unbox it and plug it into power and audio. Little did I know that this would be *ALL* I have to do!
After a quick and painless firmware upgrade, the SoundBridge detected my iTunes server and my UPnP server. I chose the iTunes one and was streaming ALAC-encoded albums over my Wi-Fi network with no gaps, drops, rebuffers, anything. All and all, less than 10 minutes to have the thing working properly.
I will note that my iTunes server is hardwired, so the half duplex nature of wireless is not causing me any problems. I have a feeling lossless streaming might not work so well otherwise.
I'm an open source engineer and work with complex systems at work every day. I have about 80 Linux machines to babysit, so I *love* when I can go home at night and have stuff just work.
I will also say that the fact that the SqueezeBox does Pandora really leaned me towards their product, but that single feature wasn't enough to justify twice the cost. I am REALLY hoping that something between Roku and Pandora is in the works.
Anyway, kudos to the Roku team for making my life a little less hectic.