Bart Dierickx from Caeleste presented his 3D sensor ideas on IEEE Nuclear Scinece Symposium in Dresden, Germany, Sep. 2008. The presentation talks about the new design approaches in 3D world. One might give up pinned photodiode and 4T CDS scheme and needs to look for other ways to suppress kTC noise.
Bart presents an idea how this can be accomplished without resorting to active reset schemes. I'm unable to understand how come that the proposed reset reduces kTC noise, but the eldo transient noise simulation in the inset seems to confirm this: