Definitely agree... we've been here before, it's 980/980Ti all over again. I don't know why people think different. I still laugh at all that talk a while ago when people though you would be getting a 980Ti for under £200 in the MM haha! Hilarious. The price the 1080 is today is going to pretty much remain where it is for the foreseeable future, and the 1080Ti will be the most expensive 'mainstream' consumer GPU in history (Titan excluded of course), circa £800-900 I am quite sure.
I am also keeping a close eye on VEGA, and with an X34 as well, I would certainly consider selling that and going AMD/Freesync if they bring a powerful enough product to market at the right price. Coupled with the cheaper Freesync monitors, that could represent a whopping saving over the Nvidia/G-Sync route.
To be fair it was more because of the lacklustre performance increase pascal offered over an overclocked 980ti. I did some some sell for £250 though.
This time round because of the exchange rate which has kept 1080 prices higher than they should and even now with Gibbos special offer some cards are still more than what you could have bought them for on launch day, this will keep 1080 prices high.
As I have said before when the 1080 launched the was $1.45 to the pound and is now $1.25. Even if Nvidia launched the 1080Ti at the same price as the 1080 was at launch it would make them £671+ here. And I doubt they will launch at that price anyway.
It will all depends how good and what price Vega is. Nvidia will have a pretty good knowledge as to hwo it will perform and what the price will be. Occasionally Nvidia get caught out on AMD's pricing and have to drop the price to match.
You have to remember that any card released today will be 17% more expensive to UK buyers than last May. On dollar price alone if Nvdia released a 1080ti at only $50 or $100 more than a 1080 then people would be cheering but with the exchange rate change that extra $100 will put them £150 more than the 1080.
Then add EVGA and Asus tax and you will see some 1080Ti being over £800.