All three of our kids have bitten us and siblings/cousins at various times. We don't use child care which is fortunate as a lot of those places are not very understanding with biters.
Having read the thread, just realised it has been a little while since our 2.5 year old bit anyone including her annoying elder brother. What you are doing sounds fine to me so just a matter of time, I think. Hopefully another 3-6 months will do it.
