Re: Bitmain looks like they're releasing a 15GH/s DASH miner called the AntMiner D3

D3 suddenly become cheap and available, what's happened? not so much profit in X11?

There is more profit in a D3 now than has been in the past 3-4 months.
Right now your looking at $300+ per month with a single D3 (Of course that is market dependent and can shift at anytime).
Previously I was looking at almost half that. I think the biggest problem with the D3 is lack of quality control on behalf of Bitmain. I have 4 D3's and only one is a quality miner, another 1 is a problem child and the last two only run on 2/3 boards.

can you tell me which coin gets you $300/month?

It's probably his electrical cost. At best, you're making $250 / month on Nicehash and you're getting ~$80 deducted as electrical cost at $0.10/kWh. That'd be near 3-4c/kWh though, much lower than the 10c average residential in the US.