Alrighty, here is a preview rendering/composition of the newest version. Added some minor particle flow to improve the feeling that we are swimming in relatively thick fluid. I also enhanced this effect a bit in AE too. I also tried to get the heart beating going on but I still don't like the vein texture... gotta do something about it... C&C as always is welcome...

(btw, DOF, Motion Blurr and the soft-body stuff for the cells are off. Also the anti-aliasing is at preview quality)