I notice a mention that people seem to think that it was a hacker or group that could have taken the power network down. In certain respects this was already reviewed by the L0pht in advance, so I would guess that certain preperations has already been made.
It's more likely that the problem with the brown out was the increase in energy used with cooling systems, especially if you look at the newer computer systems utilising extra fans.
In fact if I'm not mistaken some computer system (Intel I believe) shut down if they get to hot, so if such machines were in control over the PLC systems for the power, it would make sense that the very heat of the day could of just knocked the power out.
There is a possible solution, it's one that a certain Mr Bush didn't want to look at just yet. It's called the Environment, every car, every oilfield that burns well gas and every landfill site kicks out pollution.
The more pollution the higher the molecular weight of the air (since it includes OZone, Methane and a few other hidden nasties).
The Molecular weight increases Pressure fronts which in turn can cause storms and tornadoes.
If you don't like how the weather reacts, do something about that Kyoto Summit that you tried running from.