According to my OCA priest, "re"-baptism only happens for those coming form congregations who do not believe in baptism the way the Orthodox do. For example, Evangelical congregations do not think baptism is necessary for salvation, as much as "accepting Jesus in your heart as your personal Lord and Savior". Catholics and the Reformation churches retain that belief in Baptism. The Revivalists (Evangelicals, Pentecostals) do not, so they would need to be baptized with true baptism.
I, for one thing, want to go through Crowning. Given how shaky the RC belief is about marriage (how it can be easily annulled). Although the priest told me that it is not necessary. If you are married, you are married. Aw.