The special votes are in, and my rudimentary analysis was pretty good. I was right overall (National down one, Greens up one) and on the small scale as well: getting the Green, New Zealand First, Maori Party, and United Future votes correct to two decimal places; and also correctly predicting that Mana would pass ACT.
We won't get the full details for a couple of months (split vote analysis which show various oddities, like the 1039 voters at the last election who party voted National in Helensville but wouldn't vote for John Key personally, or the 262 Epsom voters who wanted ACT, but not Rodney Hide) but there are some things to note.
1. If either John Banks or Peter Dunne had lost their electorates, Labour would have picked up a list seat, and National couldn't have governed without the Maori Party (same if the overhang had been one higher).
2. The Special Votes wouldn't have altered have altered the no-threshold counter-factual. National couldn't have governed without either the Maori Party or the Conservative Party.
3. The Maori Electorates were massive MMP supporters (Te Tai Tonga at 78.9% for keep, the only one below 80% support); Mangere, Manukau East, Rongotai, Wellington Central and Manurewa the strongest MMP supporters among general seats, each with 70%+ for keep. Clutha-Southland were the biggest supporter of change, at 55.4%. 14 of the 70 electorates voted for change, all National-Party held.
4. The massive number of informal votes recorded in Part A of the Referendum in the Botany electorate after the count of the advanced votes has been reduced to being in-line with everyone else (leaving me to wonder if one of the people counting the advance votes there on election day made the mistake the Electoral Commission warned others about, and thought you had to vote in both parts).
5. First Past the Post topped the valid vote in Part B in 68 electorates, with Epsom voters favouring Supplementary Member, and Wellington Central voters favouring Single Transferable Vote (and SM).
6. Labour came third in the party vote in Wellington Central.
7. Parliament has three new "backdoor MPs" - incumbent MPs who were re-elected on the list after losing their electorates - Chris Auchinvole and Paula Bennett from National, and Clayton Cosgrove from Labour. Auchinvole was beaten by Damien O'Connor, who was a "backdoor MP" in the last Parliament.
Finally, it seems likely there will be a couple of judicial recounts, with Paula Bennett behind in Waitakere by 11 and Brendan Burns behind in Christchurch Central by 45. Despite their name, judicial recounts don't actually have to be conducted by judges, but can be conducted by an officer of the Court with assistants without the judge even present.