My 17 month old, who started walking at 11 months, still walks with tummy thrust out, shoulders back (normally with arms waving in the air!) and lower back curved. He isn't running yet and is still pretty uncoordinated. At the playground, he's often so busy concentrating on all the things to see that he plops down on his bum every so often, or otherwise wobbles crazily for a couple of seconds until he rights himself.
Anybody else's toddler like this? It's almost like he started walking more recently - you'd never guess he'd been walking fo 6 months!