I very proudly used to point out to DH that he was ahead of all the baby milestones in the books - but I was just more relieved that he was okay and not going to struggle. When I saw him at 10 months crawling to a pile of baby board books and paging through them one after the next (as soon as he could crawl) I knew that no other babies that age that we knew were anywhere near to doing that (or even wanting to do it). I still didn't actually connect it with anything in my mind though.
My MOM pointed it out to me after baby and I went away with her for a week - he was 19 months old. The sheer volume of stuff I took with for him to do was the first sign she needed apparently. The amount of energy I needed to deal with him was another she said. And the verbal development, the fine motor skills, the insatiable questions and the way he just learnt everything so fast were apparently all "not normal". When we got home she gently suggested that I "look into" gifted development of children. Took me 2 weeks to process what she said. Took me another year or so (and 2 VERY awesome in-the-computer friends) to help me accept and deal with it.
Made the second and third babies easier as then I knew what to expect.
BTW - I am also the one that reads and stuff and DH listens as I blather on about it. He has learnt by osmosis I think cause he really does get it
