As someone who purchased 5 Titans total, and has run 4 of them in Quad SLI for a while, if the 780 is released at $500-600 like many of the rumors suggest, I will be extremely disappointed in my purchase. I will admit, I enjoy the Titan, and actually spent more time binning each of my GPUs to see which OC'd the best and how 1 of them would perform at 1440p, so there is no bias there. However, there is no denying that if Nvidia was capable of releasing a GK110 part for nearly half the price of Titan a few months after its release, they could have EASILY cut the price of the Titan at launch by at least 25%. It was a question of "how bad do the customers want it", and had it not sold well at $1k, they would've lowered the price just like AMD did with the 7970 with its preposterous launch prices, which even though they were extreme, were child's play in comparison to Titan.
My main argument, and main issue is, after satisfying my urge to own Quad Titans and OC them, benchmark, and so on, and the fact that I've played all of the latest demanding single player shooters and beaten them, there really is NOTHING on the horizon to push such a setup, whatsoever. The ONLY thing I can think of is Battlefield 4 in conjunction with 4K, but other than that there aren't really ANY other titles being released in the near future with REPLAYABILITY, that justifies owning $4000 worth of GPUs.
I'm just glad that I'll be getting close to all of my $$ back for my cards before the release of the 780. After the 780 is out, good luck trying to sell your Titans for any more than 80% of what you paid.
Perhaps this comes down to the fact that PC gaming as a whole isn't as alive and well as I'd like it to be, and it doesn't warrant such an investment to enjoy anymore. I can play BF3 and Starcraft II (my favorite games that I replay alot) on my HD5870 at 1440p with high settings at the cost of AA, and it's almost laughable how old that card is and its value compared to all of the Titans that I own.
What I will say is that it was fun playing through Metro Last Light with the Titans, and I even used 1 Titan with a 680 for Physx and it performed really well. I do admit, I slapped my 2GB 680s back in today just to compare, and I did notice it was SLIGHTLY less smooth than the Titan, but the overall twitchy average framerate was higher which is good for a shooter. In single player titles where you spend time looking at the environment and looking for pickups and interacting with NPCs, a smoother experience with less fps can beneficial, but the games that I replay the most such as the multiplayer shooters and RTS titles, benefit more from the higher fps numbers (in reference to 1 Titan vs 2 680s for example)
Basically my plan is already set in motion, and that is to get rid of all of my Titans and watch the landscape whilst gaming on a 5870 until there is a game released that I feel I'm unable to play satisfactorily with that card.
Perhaps these are the words of someone who has had a revelation as to the blatant waste of resources for frames in games that I'll play through once and that's it.
I'm sure I'll end up changing my mind and buying 4 780s (IF they are a decent price) after launch. At least then I'd feel alot better saving a minimum of $1000 and losing barely any frames in doing so.