Filtherton, if you really were reading my posts you'd notice I'm
for homosexual marriage... but since you insist.
Children of same-sex couples will fall into one of two categories, foster children or surrogate children.
Surrogate: Issues may arise with the biological parent who is outside the marriage. The non-biological parent in the marriage may feel resentment and less attachment to the child, similar to a step-parent. Either way, there are biological ties overlapping the marriage with potential for abuse or conflict.
Foster:
Children died as a result of abuse in foster care 5.25 times more often than children in the general population.
Source
In either case you could argue that there is no maternal instinct within a gay couple. Traditional custody settlements have usually ended with the mother gaining custody because she is more capable of caring for a child, unless she is proved unfit.
Mantus, I did write a lengthy reply, then my browser hung and I lost it all. If I can be bothered I'll rewrite it in a bit.