Heard Tim Whatsisname from Coliseum the other day on the wireless talking about getting more football (and rugby)... also mentioned something about outsourcing production (ie: OSB) for events that aren't already covered/packaged (ie: EPL/PGA).
The underlying point being, as with most things - if the numbers stack up, they could put something together where they produce the coverage. Don't forget there is infrastructure within Wellington already, the only key question is the investment required to get it to HD quality (which is "reportedly" why Trackside/TAB moved to the big "A").
If they had the right sponsor/partner (ie: FFA/NZF/OFC/VW/Carlsberg, etc) it could (eventually) happen.
Would certainly expect Colisuem to be all over it when the rights come up for bidding again. Wonder if they could somehow join PLP and A League together into one subscription as well as options for both individually.