I'm like to share a little of our experience, how unschooling is working for us.
My DS6, who hasn't been schooled at all spent his day today like this:

We spent 3 hours playing Lego Harry Potter on the wii together. I felt like that was pretty excessive when I realised the time. (I forgot the time last night when we were talking about maths too so it evens out I suppose).
We played a quick board game.
Continued discussing factors and prime numbers after the discussion last night.
I showed him how to read an analogue clock and he did some exercises in a maths work book that were related.
He played some maths games on the computer.
He helped me to cook soup, hommous and stewed apples with much gusto (lol - he does love food).
He is now reading to me from Harry Potter.

Most of this was at his request, and any that I suggested was agreed to by him without any coersion, bribing, praising or anything like that.This is a typical day at home for us lately, though admittedly we don't spend many days at home.
Normally he is allowed 2 hours of screen time, either his laptop, ipod or a dvd. The wii is normally a once a week event.
I just can't ever imagine telling my son to sit and do any of this stuff, he'd probably look at me like I am nuts or something. He only does it so happily because it is his choice. If I had to coerce his learning out of him I doubt I'd have a very happy relationship with him, and he is so very clear about both his needs and interests that I'm happy with how unschooling works for us.