That's good news! I asked Cex on their official mining page if they plan to implement today.
The maintenance fee
The fee will be implemented in 1 week, which makes it November 8th 2013.
The maintenance fee is estimated as $0.30 / kW*hour:
$0.17/kW electricity cost + $0.09 data centre upkeep + $0.04 hardware repair/maintenance.
(The power consumption of 1 GHS is 1.5W per hour)
The fee will be billed in BTC per mining share. The estimated fee is 0.000000002695 BTC/share, which makes it ~4% of total mining profit.
The fee will be adjusted according to the BTC/USD exchange rate.
About the hardware maintenance:
We will charge $0.09 for the data centre upkeep + $0.04 for hardware repair/maintenance.
Handling 600+ kW mining equipment is quite challenging. This involves MANY people working at the backend, who:
- Replace dead chips
- Fix PCB issues
- Upgrade electricity links
- Improve mining software to reduce stale shares (we have stopped delivering stale shares for purchased GHS).