For those who are stil confused about the eligibility stuff here is a snip from a note posted on macrumors

#1. Customer has had a standard calling plan plus data services costing at least $68.99 a month but no more than $98.99 a month, and who has been in contract (and not had a phone upgrade) for 21 months or more,
or
#2. Customer has had a standard calling plan plus data services costing $99 a month or more, and who has been in contract (and not upgraded) in the last 12 months.
or
#3. A customer with a calling plan and data services of less than $69 who is 21 to 23 months into contract may upgrade for a fee and a commitment of an additional two-year service contract extension.