I remember that at one time Blacksad was often brought up as an example of Furry done right (I.E. Compelling characters, good story, great art, lack of perversion, etc), and I also remember I said in late 2009 that there would be a fourth book in the series out. Well it has been out for quite some time, but currently it's available only in French (Which isn't a problem for me since I know that language).
The title is 'L'Enfer, le silence,' which translated directly to 'Hell, the silence' or 'The silence of Hell', and has a cool cover of Blacksad roughed up and apparently unconscious underwater. I haven't been able to get my hands on the whole thing (there's some previews available, but only a few have the dialogue in them) yet, since no downloads are available as of yet (and if I know the internet like I do. It might not be unless translated into English), and I haven't checked my local bookstore to see if they have it (I live in Quebec, and most bookstores have large French novel/graphic novel sections for obvious reasons).