Bought a Classified 780 yesterday on Newegg for $580 (though for some bizarre reason its listed @ $700 today?). I feel like an OC 780 is "right now" the current sweet spot in the upper tier of cards. I prefer EVGA, but an argument could be made for almost any of the tweaked 780s, particularly if they are coming in at prices close to the R9 290X.
I'm impartial to the Nvidia/ AMD branding, I just want what is best when I lay down money every 3 - 5 years on computer parts. My argument this time around is that for $30 more you get the same (or in some cases, better) performance out of an aftermarket 780 than an R9 290X, AND better cooling, acoustics and power consumption. Plus I feel like I won't be exposing myself to the possibility of driver issues that often come along with a new card (not saying there are any, but history has taught me this lesson).
I knew I was getting a new card, and was actually very close to ordering an R9, but wanted to wait for the inevitable Nvidia price drops and the 780Ti release. Well the price drops came, and probably more than I expected - and while I haven't seen any performance reviews yet released on the 780Ti, at $700 I can't imagine that its performance will justify that cost. Though I certainly expect it to be at the top when it comes out. I suppose the only thing I might possibly regret not waiting for are the aftermarket solutions for the 290X, but if you let yourself, the waiting game becomes forever.
Plus AMD had its turn in my rig for the last 3+ years, I want to see how green the grass is on the other side this time around.