My daughter is a March '04 baby, and she didn't get down on the ground outside on her own (walking) her very first winter. In the end, she didn't even start walking until 16 months, which was summertime for her. Her first winter WALKING she was about 20 months old (20-24 months or so) and we got tremendous use out of a pair of Ecco "first walker" boots. They weren't specifically snow boots, but they were great shoes for any walking she did outside. Well-made, with extremely flexible soles. (They were some little red lace-up boots.) She wore them all fall and most of the winter....she had been walking since summer at that point, though.
We also had a pair of zip-up See Kai Run boots, and they were really nice. (You can get faux-fur lined or plain leather, and the soles are very flexible rubber.) We used the Ecco and SKR boots as shoes (they weren't insulated waterproof snowboots.)
I did try some snowboots from LLBean and Lands End, but the sizing was way off and I had to return them to get the right size. In the end, the Bean boots were outrageously stiff and even once we had the right size for her, she couldn't really walk in them (I just returned them.) I stuck with a pair from Lands End which she used whenever she was in her snowsuit and actually playing in the snow. But she never walked all that great in them, either.
This year (she'll be 2.5 next month) I'll need true snow boots as I know she'll get out and play even more. But I'm going to stick to something flexible and water resistant, something walkable and a good fit.
I'd advise you to be conservative, wait and see what you actually need/what your child's mobility is like. My daughter still spends most of her time in the Hanna Andersson slipper socks from fall through spring, if she's not outside. She used those and Robeez all through her first winter, and we basically were carrying her anytime she was outside.
