What the deuce are you talking about? It doesn't matter if you buy it on the day of purchase, or 364 days later. Either way, your warranty is 2 years. In fact, if you buy it later, you're missing out on the phone support, which is only 90 days from DoP without AppleCare.
As with all applecare agreements it only EXTENDS the cover from day of purchase to two years.
This means regardless of when you purchase it you will only get two years overall coverage.
(Unless shanepod has something up his sleeve....?)
If you are going to get it then i would advise to get it now, i have found that when dealing wih apple customer services you seem to get faster and overall better service when they know you have applecare.
Some credit cards will double the manufacturer's original warranty for a max of 1 year, which would give you 2 years total for Apple. This is for Canada and the U.S., I don`t know if this works across the pond.