Earlier I had asked if anyone knew or can guess the cost to BA of the IT glitch last May.

I found the answer today in a news report. Mr Walsh told the media that it will cost BA about $ 102 million USD. (75000 pax affected). A stiff cost for unplugging and plugging backa cable in the power outlet. Wonder what the damage is in PR & goodwill.
The Chairman assured that we will learn from this and apply it to our future processes (paraphrased). Now only if they would do that to plaints heard here on FT BA can return to its leader position.
I do have a 1.2 million USD suggestion : When I take US appliances that use 110 volts only to countries that use 220 volts, I have a large warning tag at the plug " WARNING, USE TRANSFORMER".