As the only international airport serving the Central Otago region, Queenstown Airport is constant hive of activity and among the busiest airports in New Zealand for passenger traffic. For the year ending June 2011, Queenstown Airport handled 924,248 airline scheduled passengers according to Wikipedia.
Qantas, Air New Zealand, Jetstar and Virgin all operate routes from Australia (Brisbane, Sydney and Melbourne), with extra flights scheduled in peak winter and summer. Domestic routes include Auckland, Wellington and Christchurch. Flights are limited to day-time only and can be restricted heavily by weather conditions in winter. On occasion, flights get diverted to either Invercargill or Dunedin due to low-lying fog or stormy weather, leaving passengers with a long bus ride to complete their journey.
The terminal itself is every expanding. There are numerous retail shops (with duty free options) and car rental companies, as well as an airport lounge, cafe, currency exchange and multiple ATMs. Parking is free for 20mins and paid there onwards. They also offer free wi-fi throughout the airport.
It’s not just passenger flights operating out of the Queenstown airfield, there are a large number of fixed-wing and helicopter scenic flight operators too, taking tourists as far afield as Milford Sound.