Ethereum, Monero and Zcash is where it's at.
Some people are also mining ETC.
Right now out of all these Monero seems to be the most profitable coin according to coinwarz.
If you're looking to buy the 470s now, don't. Wait for the Vega GPUs instead.
Vega seems pretty far out with only a bit of news of it at CES. I guess it is more about snagging them around sales, large hashrate difference between 4-8gb?
Vega is actually coming this quarter, most likely in march though. And there's no difference, but 8GB cards
might have better memory chips that overclock slightly more and/or have smaller timings.
If you do decide to buy 470s, get some that have good VRMs, because they overclock much higher & are slightly more power efficient. Asus Strix > XFX GTR/Black > Sapphire > MSI = Reference > Gigabyte > Powercolor
Strix's VRM is overkill for such a chip and expensive, XFX/Sapphire are the best value, the others are crap. Gigabyte and Powercolor are legitimately worse than the reference design.