Looks like Telecom XT have dropped all the XT data plans except for a 2GB and 4GB plan. The plans came in over Christmas (??)

http://www.telecom.co.nz/mobile/mobilebroadband/plansandpricing/monthly

Mobile Broadband 2GB      $49.95 on a 24 month term      $59.95     
Mobile Broadband 4GB     $69.95 on a 24 month term     $79.95   

get an extra 4GB FREE when you sign up to a 4GB plan on a 24 month term. Offer expires 31/01/2010.

Looks like a good deal, 8GB of data month for $69.95/month with a free T-STICK to boot :-)

I was on the 1GB plan on my iPhone, but it looks like I can get the 2GB plan for the same price. W00t!