Been through a few reviews and main takeaways:
* 1060 wins for DX11 by a little bit (generally up to 10%)
* 480 wins for DX12/Vulkan by a lot (except RotTR)
So for me, 480 seems better value and is more balanced. For a little bit less money you get a little bit more RAM. For a little bit less DX11 performance you get significantly more DX12/Vulkan performance.
Only thing I like the 1060 for: I loved that EVGA low-profile short version. With the low power of the 1060 I can see it being a huge hit for small form factors.
With this post, I've joined the club of people quoting themselves

Based on the above, there's only 1 good reason for choosing a 1060 and that is: it's a stop-gap card and I will upgrade again in less than a year to Vega/1080ti.
People which can afford to do this probably won't care about a £50 difference anyway, and can enjoy their current DX11 games a bit better. By the time DX12 becomes a problem for them (too many games using it) they will have switched to a new card (and not care about the 1060 resale value plummeting).
However, the vast majority of buyers in this price range are price-conscious and upgrade on a longer cycle (2 years min). For them the 1060 makes no sense at all. Around mid-2017 they will be stuck with a card that performs badly in the DX12/Vulkan games AND has lost its resale value (who in their right mind will buy a used 1060 when DX12/Vulkan are the majority of games).
GTX 1060 is just way overpriced for what it offers. RX 480 is the way to go.