Basically US is not good for long term investment. So, you can buy whatever currencies.
According to UBS Wealth Management Reasearch's global forecast dated 16 Feb 09, NZD will have a potential gain of 15.74% in 12 months period. However, it will drop in 3 months' time. So, you may wait & buy it when the rate (NZDUSD) at about 0.5.