Leave it on or turn it off?

As another CA resident, I must also take brown out into consideration when the voltage dropped below 90V. I used to leave my pre-amps and Marantz SA-1 on all the time until I blew the fuses 3 times in a row since the summer started. For those who owns the SA-1, a blown fuse means at least 2 weeks of down time since the fuse is hidden inside the power supply and is not a user-servicable part. To me, the sonic improvement simply isn't worth it (at least when we are still in the crisis situation).

Seems to me that leaving any equipment on leaves it subject to things like line surges and nearby lightning strikes. Am I wrong?

Unless you have surge protector. But still every time the hair dryer is turned on upstairsm the loud humming noise from turned on amp scares the hell out of me. I turned my stuff on about 1 hr before listening session.

DWPC,
I think that as long as it is plugged directly into the wall and not through a power conditioner, we all run that risk - on or off. It's those dang wires!

Spectral recommends explicitly that their DMA-360 amps not be left on unattended for long periods, because of potential speaker damage during brown-outs or power outs. Check with Classe on their recommendations for their amps.
Dwpc, high quality surge protection should help, but there are no guarantees with lightening strikes.