My concern with Polaris 10 is 2-fold.
1) Even if at stock speeds it's ~ Fury / 980, will it have the same amazing overclocking headroom as the 1060Ti/1070?
2) Combining point #1, if Polaris 10 is $299, it might not look so stellar against a $379 1070. In other words, if 1070 is beating Polaris 10 by 20-25%, but the 1070 also has 20-25% overclocking headroom, it's still worth the premium to get the 1070.
In fact, even if Polaris 10 and 1070 are simply tied, many people would pay $80 extra for NV alone (recall $299 280X vs. $399-450 770 2-4GB). I bring this example a lot because it's exactly what happened in reality when the Tahiti AMD card was substantially less expensive throughout the entire duration of R9 280X vs. GTX770 generation.
Perhaps AMD wants to see where AIBs price 1070 and what the availability of 1070 is before they finalize the pricing for Polaris 10. As far as GPU clocks are concerned, I am confident that technically speaking the specs for Polaris 10/11 have been finalized. This is probably why AMD is so quiet right now because the $379 price of 1070 and Pascal's overclocking headroom on air caught them by surprise.
Maybe AMD will surprise and launch Polaris 10 at very aggressive price points such as $229 and $279. This way it'll be completely out of the way of 1070 and NV will have no response whatsoever for months.