The current really does consist of a flow of electrons. It's true that under typical conditions (say a 10 A current at 50 or 60 Hz in a wire with a few square mm cross section) the electrons don't go very far before reversing directions. Under the conditions mentioned, roughly 10-3
cm would be a good ballpark estimate of the oscillation distance. That's still large compared to an atomic size (~10-8
cm) or the distance an electron travels in room temperature copper before scattering (~10-6
cm). Nevertheless, it's small compared to the length of a typical power cord.
The errors in that youtube, by the way, mainly concern the statements about the alleged enormous costs of generating and transmitting dc power compared to ac power. The generation costs are very similar. Cars, for example, used to have dc generators although now most have switched to slightly more efficient ac generators. Small motors (which are generators when you turn them and extract current can easily be found in cheap ac or dc models. The main reason for using ac power is that it allows a simple device (a transformer) to convert between high and low voltages. Since in order to transmit a lot of power through small wire you need high voltage (letting the current be small) the ability to convert to high voltage for transmission and back to lower voltage for use is very important. More elaborate devices are now being used in a few places to allow conversion to and from high voltage dc. Other than the conversion difficulties, dc makes even more efficient long-range transmission, because it does not emit electromagnetic radiation.
p.s.-Temporarily posted without the usual check, since Lee's in Paris.
(published on 11/27/11)