This is an interesting development. Presumably NZ will put their code on this flight (given recently announced codesharing agreements with CO) so not a totally lost opportunity?
Interestingly (for me, anyway, living in NYC and always interested in 1-stop options to NZ), AKL-IAH-NYC will be a considerably more direct routing than the current options via the West Coast, assuming that CO can resolve the ETOPS challenges on the route - for more on that, see the
featured map on Great Circle Mapper. In an ideal world I'd rather be on NZ metal, but as US airlines go CO is definitely one of the better ones, and their lounges are genuinely habitable and come with free alcoholic drinks and wifi (let's hope they both survive the merger with UA, which currently offers neither).