I think any action that can help promote science in French would be a good action, and it would certainly be something we would support.
The Canadian Association for Graduate Studies is a bilingual association, and we're making more and more room for the French language, whether in our working sessions or in our annual conferences.
A French-language multidisciplinary scientific journal would indeed be interesting, but we mustn't forget that the French language can also be a barrier to scientific dissemination in some cases. I'm thinking, for example, of a physicist who decides to publish his thesis or dissertation in French. He could certainly do so as a French speaker, but this would probably mean that his work would remain on the shelf.