Hi RT - sorry about link not working but you found the longer version anyway
The woman (in the rainbow shirt) is another MP who had fought for the bill to be read and passed. She was the strongest supporter of the bill. Her name is Louisa Wall (if y Wikipedia her you will find out all about her and the Bill etc)
The song sung is called Pokarekare Ana; a Maori (indigenous New Zealander) song, all about love. The words are below. Very beautiful song, and very appropriate for the occasion "oh girl come back to me, I could die of love for you"
After all, it's what it is about isn't it - love - as opposed to 'gay marriage'.
http://en.wikipedia.org/wiki/Pokarekare_AnaIf you googled Hayley Westenra's version it is probably my favourite.
Edited to add the vid (couldn't resist)
http://m.youtube.com/watch?feature=kp&v=9GXua6gD4HcMy favourite line: 'I've written you a letter and enclosed it with my ring; so your people could see it how much I'm troubled for you'. In this context that line speaks to me saying how it doesn't matter if the love happens to be between two people of the same sex; the author wants others to know it is just the same heartbreak and 'troubled for' as the love and separation of two people of the opposite sex. Love is love, regardless of who it is between