This rumor still makes no sense many days after it was originally posted on Videocardz.
Why would Nvidia compete with themselves? They own the high end, and there's no reason to undercut their own New Titan X with no credible competitor to try and beat. That's what the Ti is typically reserved for, after all.
How exactly are they supposed to get to 10 GB of RAM? That's not a multiple of anything at all, unless they are gunning for a 320-bit memory bus on the Ti to fit in between the 256-bit bus on the 1080 and the 384-bit bus on the New Titan X. I guess that's the only sensical theory.
I'm assuming this thing will start at $999 to slot between the $599 1080 and the $1299 New Titan X. With no competition, it wouldn't make sense to displace their own 1080 in pricing and no one should expect that they will do this.
Either way, I'm not crying about my 1080. I'll wait until Volta before I upgrade again at this point.