I doubt anyone will be buying 1070's than outperform non reference 980ti's for under 370$ anytime soon. The cheapest we've seen is the evga acx3 1070 isn't it? At like 420-430?
The default cut on the 980ti may have only been 125$ but the prices on newegg are far lower. I just grabbed a 980ti msi gaming golden edition for 369$ on newegg. Should last until 1080ti or hell maybe just use it until 1180