right, the ffgl stuff is not compatible with vvvv unless someone finds out how to bridge directx-textures to opengl-textures and vice-versa (which should be possible somehow) and finally implements this in vvvv. so don’t expect ffgl to work with vvvv anytime soon.
but (and here starts the advertorial) you may want to consider that there shouldn’t be anything you can do with ffgl that can’t be done via vvvvs effects (which are also kind of standardized and can usually be shared among applications with some minor changes).
it is probably no good idea to base your decision for a software on the support of ffgl. if you are planning on rather traditional vjing with lots of prepared videoclips that you mix and add effects to vvvv is not the best choice.
on the other hand if you are more into multiscreen/realtime/generative/3d blabla then vvvv is what we make for you.
what i am planning is not normal vjing, but more a production job… a very exciting film remix job for coldcut. its secret for now but i will come back to the vvvv community if it goes ahead, as i think it is something you hedz will be interested in.