So BFL is finally sending me my 60 GH/s miner and I am trying to calculate profitability to determine if I should sell it or if I should mine with it. I am using: http://www.bitcoinx.com/profit/

With the default settings, except wattage I bumped up to 400 Watts, Hash rate to 60 GH/s, cost of hardware to 1,500 and time frame to 12 months. I am getting a profit of just under 8k in the first year, but I must be missing something. The deal seems to be too good. Can someone tell me what I am missing?


Bitcoin difficulty: 112,628,549
Bitcoins per Block (BTC/block): 25.00
Conversion rate (USD/BTC): 130.16
Hash rate: 60 GH/s
Electricity rate (USD/kWh): 0.15
Power consumption (W): 450.00 (computer on some sort of inactive mode, while miner at 300+? dunno if this is accurate)
Time frame (months): 12
Cost of mining hardware (USD): 1500.00
Profitability decline per year: 0.61

Results

Difficulty:    112,628,549.00
Mining Factor 100 :   0.06 USD/24h@100MHash/s as in these charts
Average generation time for a block (solo):    93 days, 7 hours (can vary greatly depending on your luck)
Hardware break even:    47 days
Net profit first time frame :   7957.73 USD
Coins per 24h at these conditions :   0.2679 BTC
Power cost per 24h:    1.62 USD
Revenue per day:    34.87 USD
Less power costs:    33.25 USD
System efficiency :   133.33 MH/s/W
Mining Factor 100 at the end of the time frame:    0.04 USD/24h@100MHash/s
Average Mining Factor 100:    0.05 USD/24h@100MHash/s
Power cost per time frame:    591.70 USD
Revenue per time frame:    10049.43 USD
Less power costs:    9457.73 USD