Twiwi
A user of the Twitter social media service who is from New Zealand. New Zealanders are affectionately known as "Kiwis" (named for a flightless bird native to New Zealand, not the kiwi fruit), so Twitter + Kiwi = "Twiwi."
Wikipedia Kiwi page:
http://en.wikipedia.org/wiki/Kiwi
Wikipedia Kiwi page:
http://en.wikipedia.org/wiki/Kiwi
Jim from Auckland and Susan from Christchurch met other Twiwis from both the North and South islands at the all-New Zealand Tweetup.