I think it depends! For instance, if you have cable tv, chances are you use a all-in-one remote and turn off the cable when not watching, but the tv itself is still on. So, when you turn the cable, the tv is already warmed up and you get an immediate picture. But, the tv is on all the time, and it wears on the tv and does draw some power.
Here is another thought about unplugging, though. Our house has been struck by lightening once, and had a major power outage from a storm. In both cases computers were plugged in, but off, and both were fried. In the strike, which hit our chimney, the charge traveled down through the electrical lines, phone lines, cable tv. We had to replace four phones, two cable boxes, the interior cable lines and junctures, one interior phone line/jack, two garage openers, the tv, a toaster, etc.
Yes, we had surge protectors on some things. The computers were lost because the modem lines were plugged in, power coming through the phone line got them even though the surge protector kept it from coming through the power line.
When in doubt, disconnect.
