1080p: In my mind, the consideration of children is no reason to deny homosexual couples the ability to marry. Especially given that there are a number of other reasons why couples desire marriage and that the phenomenon of children being raised within heterosexual marriages is unlikely to ever change or shift to abnormality.
I don't have any personal views to add to this, but just as an observation I find it interesting that you refer to 'homosexual' marriages. Previous posters have suggested - quite rightly in my view - that in a political or legislative context marriage is nothing more than a legal contract between two individuals and hence I would argue that there is no such thing as "homosexual" marriage. In light of that, I prefer the terms "same sex marriage" and "opposite sex marriage".
Yes, I know, this is all just semantics, but this debate does seem to have a tendency to drift into irrelevant territory when certain language is used.