Running the risk of "piling on" here...but I think it's a great conversation (regardless of Roku's plans).
dupondt... While I respect and understand your opinions, there are a couple of items I have to take issue with.
b. only very few portable music players (aka MP3 players) support them, the most popular ones are not among these;
While I don't disagree with this statement, I would suggest that those who really want flac support (myself included), don't want it because of their portable music players. Roku's products are about home stereo/hifi (IMHO). PMPs are and always will be a compromise of convenience over sonic quality.
none of the most popular programs for ripping CDs supports them out of the box (not even Winamp does when it comes to ripping).
I think you're mistaken about Winamp. With current version (5.52) native flac support is present, and one can easily rip CDs to flac (although I don't actually use WinAmp for ripping). But I just tested it to be certain before writing this.
Now having said all that.....yes, transcoding from a server is always an option and works fine in most cases, even on a relatively low-powered NSLU2 w/Firefly (if your network connection is wired, that is). But transcoding is always a compromise at best, and as has been suggested...native codec support in a client device has advantages (bandwidth and server cpu utilization reduction among them).
I use flac for various applications and will continue to do so. For example...for anything that is not easily replaced, like the tracks that I convert from vinyl, I will choose to use flac. I will also be transcoding those same tracks for transfer to my iPod, and for now, for playing on my Soundbridges.
For a devices like Rokus, I don't really think it's far-fetched at all to suggest flac support....after all Roku *does* support two very proprietary lossless formats (ALAC and WMAL), which also fall victim to your arguments about native support, portable support, and so on.
But to reiterate, my comments come from approaching my Soundbridges as components of my home stereo equipment...not so much as an internet radio, or portable device.
Cheers and Best Regards