For me, it's just a fact I throw out to emphasize that it's my life, not just a hobby or a job. It's seriously part of who I am, right to the core.
For the record, it was 4th grade for me... About 10 years old. Had it been younger, I'm sure I'd still have glommed onto it just the same... That was just the first exposure I got. Hint: Expose your kids to things young. It could make a big difference in their lives.
The discussions below about sports are interesting, though. Lots of kids seem to play basketball even though (or arguably because) the stars are put on pedestals. But not everyone plays basketball.
Starting to program at the age of 6 is nice and good(if that is out of curiosity), but for me - I'd say - wait for sometime,do the things that you are supposed to do at that age, and when the time comes to be different, you'll know and follow it then. There is no point in bragging about when a person started to code.He might miss out on a lot of things as a child which might make him a different person and constrict his 'social' network. As a child spending more time in the programming world is not desirable, after all we all are programming towards making things work like humans would work, and we are missing out on the 'being human' part by programming in the time in which we are still growing as a human?