Soldato
From what i have seen, it still needs LN2 to get past 2.1ghz stable
Many cards do over 2.1 on air. Radox has one that does 2.2ghz. Both mine sit nice at 2.1. One card does 2.14.
Even a screenshot posted a whileback with kingpin on LN2 at 2.8ghz.
With regards to loosing value. I bought both my 980's for £425 a week after launch. Sold them after the 980Ti was released for £330 each.
980Ti I paid £600 each. And got £350 each.
1080Ti to 1180/1170 you will loose a lot more than 1080 to 1080Ti. Main reason is the Ti will be more expensive, So the 1080 still has its place for people not wanting to pay as much.