Also I just lifted this from the gov site which absolutley backs up the info posted here - again thanks everyone.
When adoption is final. When the adoption becomes final depends on the type of immediate relative (IR) visa under which the child enters the United States.
- IR-3 visa. The adoption of a child who enters the United States on an IR-3 visa is treated as final in the year the competent authority enters a decree of adoption. The competent authority is the court or other governmental agency of the foreign country that has jurisdiction and authority to make decisions in matters of child welfare, including adoption.
- Other IR visas. The adoption of a child who enters the United States on an IR visa other than an IR-3 visa is treated as final in the year in which a court of the state in which the child and parents reside enters a decree of adoption, re-adoption, or otherwise recognizes the adoption decree of the foreign country.