my div guess .0021
I'd say .0025
I'll split the diff, would be 0.0025 without hosting costs, so guestimating 0.0023
Hosting is $0,25/kWh. The new hardware runs at 0.785 watt/GH/s, let's assume overall it's 1 watt/GH/s. Let's go with a price of $600 per Bitcoin.
At current diff, we should mine 0.00505 BTC per share in one week. Hosting cost would be about 0,00105 BTC. 50% of 0.004 is 0,002 BTC.
Now GH/s per share might be slightly above 15 GH/s (waiting for a statement from cryptx on that), watt/GH/s overall might be a little better in reality and the bitcoin price might go significantly higher over the next week, which further reduces hosting costs.
But 0.0025 might have been a little optimistic. stompysteve's guess is probably spot-on.