@ somebodyspecial,
First generation of GTX Titan was 1.8x it's Core Count of it's cousin, the GTX 680. Second Generation GTX Titan, or Titan Black only had a higher frame buffer and 64 bit floating point precision from GTX 780 Ti aka GTX 780 "Titan". GTX Titan-Z is 2 GTX Titan Blacks on a single PCB for 3x the price with a tigher frame-time variance between GPU 0 and 1. GTX Titan had nothing more to offer that justified it 3x price tag, and NVidia needed to get "a" dual-GPU premium of it's own because AMD didn't drop the ball with the R9-295x. NVidia Consumers, their mouths almost literally dropped when they read the release of R9-295x for the first day. If you paid for a Titan-Z, you're really just paying more money with the same features as a 2x SLI GTX Titan Black.... At best, GTX Titan is overkill-premium gaming hardware with some DP action for rendering, folding, etc... If I were to pay $3,000 or more, I'd prefer getting a W9100 just for the 16 GB Frame-buffer for actual content creation and rendering. Anybody who owns a GTX Titan-Z, it's just for bragging rights, but that doesn't last long. In addition, it doesn't say much about the owner...
@ Hardcore_gamer,
GTX Titans are for stupid people with fat wallets. GTX Titan Z would have been an ideal card if it were an actual Workstation card. It had the workstation graphic card price tag. Sell it for $2,000 more with the rest of the goodies, and its sells would probably go up. It's 1/4 DP the GFLOPs x2, at 800 Mhz per gpu, it would put the Tesla K40 to shame as an accelerator, but the K40 would still rocks that 12 GB Frame-buffer.