For those who don't have time to read it, the basic points (I think) are these:
1) since WWII, there has been an increase in the amount of human free time available.
2) for a long time, a lot of that free time was soaked up by TV--most people passively consumed entertainment (or sometimes information) but did not significantly contribute to it.
3) with the rise of participatory projects on the internet (the author mentions Wikipedia as an example, but things like Flickr and Youtube occur to me as well) it has become more and more possible for people to direct their free time into producing and sharing information (and entertainment).
4) 1% of the present TV-watching time would add up to 10,000 Wikipedias.
5) kids are very familiar with the participatory nature of entertainment (the title is about a small child mistaking a TV for a computer and looking for the mouse so she can give her input) and thus presumably information. The author implies that the trend for participating will only increase.
I find this both fascinating and hopeful. On the other hand, it looks to me like this may be one of those ideas that takes off on the Internet because it fits in with our worldview ("Progress is good; participation is good; technological progress makes more participation possible; we'll put our brains together and make the earth a better place.") but maybe not so much because it's true.
What do you think?