This rate is incorrect. Have a look here:

http://www.google.com/finance?q=USDISK

You see that for the last day of the graph the rate is a lot higher. However, if you look again tomorrow, you will see that it still is only the last day that is shown higher. The rate you can get is the lower one, currently fluctuating between 120 and 130 ISK per USD. (Actually, you will get an IATA exchange rate that is set every week, but which will be approximately the lower rate.)

The other, higher, rate that is shown, is an implied exchange rate of some kind of off-shore trades of financial products (at least, that's the way I understand it). Since Iceland has currency controls in place, these rates can diverge.

I was in Iceland a week ago, and the lower rate is also the one you get when you pay by credit card.