I installed it on my Ubuntu machine and it seems to work just fine.
However, after syncing with the ereader it seems to have lost two covers (both books I bought recently) - I see a big ugly cross on them. On the reader the covers are still there, but now I am worried about syncing again. Updating my library doesn't bring the covers back.
Also, syncing replaced the bookmarks on the reader with the ones from the desktop application, which is not the behaviour I would expect. But that is probably not something related to the Linux software in particular.