I have a Gtx 970 atm but I would like to know people's opinions. When do you think the 970 will be outdated (kinda is already) and games will recommend Gtx 1060 or 1070 for max setting instead of the 970?
Depends on the game and the resolution. Should run newer games for a few years, although not at high settings for all of them. Use it, when it's slow, look for a newer card. Why bother with it till you actually start having issues.