There are better sources than that on precocity in young children. I'll have to find some references for you. (They may not be found in time for the edit window of this comment, so feel free to write me off-forum if you would like those.)
In general, early reading is less remarkable (in English) than people think it is, because with the right materials[1] English can be seen by a young learner as a rather consistent writing system that is not insuperably hard to decode.
That said, my four homeschooled children, the first two of whom are strongly bilingual in Chinese and English, having lived in Taiwan in early childhood, were early but not strikingly precocious readers, and all my children were learning a lot of other things besides reading in their early childhood, of which chess was perhaps more conspicuously precocious than reading. Earliness is less important than long-term solid development of skill, and it sounds like the parents of some of the HN participants here who have personally observed examples of very precocious reading were well aware of that.
In general, early reading is less remarkable (in English) than people think it is, because with the right materials[1] English can be seen by a young learner as a rather consistent writing system that is not insuperably hard to decode.
That said, my four homeschooled children, the first two of whom are strongly bilingual in Chinese and English, having lived in Taiwan in early childhood, were early but not strikingly precocious readers, and all my children were learning a lot of other things besides reading in their early childhood, of which chess was perhaps more conspicuously precocious than reading. Earliness is less important than long-term solid development of skill, and it sounds like the parents of some of the HN participants here who have personally observed examples of very precocious reading were well aware of that.
[1] http://www.amazon.com/Teach-Your-Child-Read-Minutes-ebook/dp...
http://www.amazon.com/Lets-Read-Linguistic-Leonard-Bloomfiel...
http://eps.schoolspecialty.com/products/details.cfm?serieson...