Um, this number sounds high. My recollection is that there is a $20/month difference in price so you are effectively paying an extra $480 towards a phone over two years. If the difference in up-front cost for the device is less than this, buying off-contract is cheaper.
There's a $40/month difference in price if you use google voice for texting and get the $10 data plan. (You change your phone online to one eligible for it and change the APN on your nexus one)
