I basically follow this pattern:
start from 0.1.0
when it's ready I branch the code in the source repo, tag 0.1.0 and create the 0.1.0 branch, the head/trunk becomes 0.2.0-snapshot or something similar
I add new features only to the trunk, but backport fixes to the branch and in time I release from it 0.1.1, 0.1.2, ...
I declare version 1.0.0 when the product is considered feature complete and doesn't have major shortcomings
from then on - everyone can decide when to increment the major version...
