I'm working from exactly the same position as Vrette & Maillaxa, FLAC is my primary -"gold copy" - format & I'm reluctant to have to think about transcoding to another format.
I've played my FLACs with partial success on my N800 with Canola but the file & playlist management is severely impaired and that's something I've brought up on another post.
I'd really like to see Canola implement an MT-DAAP client as my home setup is is built around Firefly Media Server hosting & streaming FLACs out to varous clients ( it does this as a WAV stream ). Alternately, maybe Firefly might get uPnP functionality first.
However, Canola has competition in the maemo space - I tried Mediabox Media Center and It does FLACs pretty good. It listed my albums as found in the selected directories, it displayed artwork as per the thumbnails in the folders/embedded Images and read the playlist files. Only gripe so faaar is that it's not playing a playlist in track order.
Brazil (iNdT) & Germany (Martin Grimme) should get get together on media player dev to help each other out and deliver a blindingly great media tool.