I vote for New Zealand too. The pack looks great, and more importantly they seem to have a good strenght in depth, which is not the case with other top teams.
England is the best team at Twickenham, but take them away or take 3 or 4 players out, and what do you get? This was the case with New Zealand in the recent tour and they were up to it.
I think that, given the location and the time of the year, the next WC will still be for the southern hemisphere.