You're right, but the last one was published in 2014 and there hasn't been any new one announced, so I'm quite skeptical.
However, you don't have to wait for vol. 11 to get to the great stuff. The first really great stories should be in vol. 3 or 4 of the Dutch edition - basically as soon as the Marsupilami has fully developed as a character.
EDIT:
Vol. 3 is certainly great: "De Dictator en de Paddenstoel" is one of the most well-received stories, afaik (I certainly loved it).