Its nice when your toddler can do things much earlier than anyone expects, especially if you more or less miss the frustration that marks the terrible twos because their communication is already so good that they don't feel frustrated.
And when competitive mothers at the mother and toddler group start comparing development, you know they won't want to compare progress with you.
However, it begins to turn on its head at school. You child is exceptional and unfortunately, schools don't really cater for the exceptional. That means frequent trips to school to try to encourage some sort of response from the teachers. there is some funding for extra help for children who struggle to pick things up but nothing for the other end of the spectrum and the system just isn't set up to encourage schools to help them. Its all "no child left behind".
So, it will be frustrating watching your child tread water for prolonged periods, not to mention worrying when you see the impact this has on your child.
Then there are the potential issues of difficulty finding friendships, asynchronous development, boredom at school and perfectionism.
For the parents, its just hard work (and potentially expensive) trying to feed a voracious appetite for knowledge at home.
For all the pride and amazement I felt when my children were little and could read etc with alarming ease, I realise now that our lives would have been much easier if they had just been a little less clever.