Looks like much of the leaked info was slightly wrong - all the tech channels which saw it in the last couple of days are saying 35% performance increase overall compared to the 1080, and pricing of 699$ USD, which is 500 USD cheaper than the Titan XP.
The price for 1080s and other cards is dropping too, the 1080 will be 499$USD or less sometime in the first half of March, and there is a couple new 1060 overclocked SKUs coming too.
The 1080ti won't have the $100 premium for the founders edition either, so early buyers won't get that hit which was applied to the 1080 founders cards.
MemEx expects them in March, but no more accurate date/info so far. Expensive, but not as bad as I thought the 1080ti would be, considering it'll likely perform nearly as well as the Titan. That 35% increase is important for VR users, as SLI doesn't work with VR games (I think there are 2 that work right now), and even a single 1080 can see performance drops in many VR games, at least that's my experience with both the Rift and Vive. Also for 4k gaming, the performance increase will help significantly.