Well, I’m going to keep an eye on it then But I must say that I’ve seen several similar projects over the last few years and they always have a great initial development speed but slow down when the package becomes larger. I think it is because Blender was initially developed as a commercial app that is has a really mature feel to it and it is currently the only package tmo that can compete just a little with the big commercial boys. And that is not just for the software, try to find another Open Source 3D app with the same standard in user-documentation (meaning: the printed manual) as Blender 8)
Getting back to the original question - K3d vs Blender
K3d has some great features, I’d like to see something like it’s tutorial system in Blender. Things like spherize are handy also. You can animate (with keys and IPOs ANY variable) However, K3d doesn’t have an armature system, so animating charachters is difficult to say the least.
Over all, Blender simply has more power and flexibility, but K3b has the advantage of using the renderman standard and works very well with BMRT (if you have it) and Aqsis, and can use Pixie or 3Delight as well.
They take very different approaches to modelling, K3d is easier for simpler things, but Blender is probably easier (and faster) for more complex shapes.
If I had to chose only one app, I’d take Blender. Thankfully, I can afford both