Not sure I see the problem with $380 for the 1070 if it really delivers 980TI performance. Add in a few mail in rebates, some competition from AMD and you could be paying $325 for a 1070 in a few months (though 380 sounds fine to me). The 980TI has been a 'slickdeal' at $550 for the past 6 months. What more do you expect?
Just ignore the founders editions -- stupid cash grab by Nvidia.
It depends on availability.
If all we have are "Founders Edition" until July/August then the 380$ is basically a lie (as is the 600$ price of the 1080).
If all this founders-only nonsense release is indeed true, this really feels like nvidia just trying to one-up AMD, as they "released first", as otherwise I don't really get why they had this press event. A paper launch for a limited (and expensive) edition 1080/1070? meh.