Although the situation may be somewhat different in Australia, from the standpoint of US Civil (Domestic Relations) law, neither of the two cases cited (20 Sep 07 - 06:42 AM)
have anything to do with the sex of the parties.

In the first case, a "biological father" who was not legally married to the mother is attempting to assert "parenthood," despite the acceptance of parenthood by the preferred (married?) partner of the mother. Cases of this kind are not particularly rare¹, and this case certainly wouldn't have been noted by the media except for purposes of promulgating notoriety over the "gayness" of the parties. The attempt to assert "four parents" has no standing in any US civil law that I've heard of, regardless of the sex of any of the parties.

A simple compromise, although unlikely to be deemed acceptable by the parties, would be to name the "other couple" as "god-parents" and give them some (limited?) power of attorney to participate in the rearing of the children - but even that has nothing much to do with sex or sexual preference.

In the second case, two "parents" asked for one child and got two. That happens quite commonly in cases of artificial insemination, and this is certainly not the first case in which the parents have attempted to hold the doctor liable. Again, the sexual preferences of the parents have NOTHING TO DO with whether the case has any merit, and the case would almost certainly have passed unnoted by the media if not for the sensationalist opportunism evident. Multiple prior cases in the US, mostly with more conventional couples, would suggest that their chances of winning anything from the doctor will be written up in a judgement containing references to "snowballs" and "hell."

Maybe the couple in the second case would like to offer their "extra" child for adoption by the guys in the first?????? (OK - sarcasm should be limited, and apology given.)

¹ A spin-off result of "genome projects" in which people submit their own DNA for purposes of tracing ancestry has been the observation that a startling number of people (>>10%? according to several reports) cannot be the biological offspring of the father who raised them - regardless of how "conventional" their family background.

John