I'm blowing the EIQ trumpet, but check out http://www.electroiq.com/index/Semiconductors/sst-blogs/chipworks-blog-display/blogs/sst-blogs/chipworks/post987_3596488420747370540.html for plan-view images and more discussion.
Why Samsung did not follow the existing naming guidelines? They are trying to create confusion by coming up with their own naming convention. I guess all the chip manufacturers should also append to letters to their naming convention
1) AA - Above world wide average
2) BA - Below world wide average.
This will give clear picture if the shrink is real or just hypothetical.
Interestingly, this can also be considered equivalent to a 4F^2 cell with F=46 nm. I wonder if they could not directly pattern at the 38 nm 6F^2 design rule. Still, they could have done something like 42 nm and still get cost advantage.