Should I trade in my iphone 4s?

I got my 4s in May since my old phone broke. When I checked on amazon on how much my trade in value is, they said I would get back 415 dollars in an amazon credit. But only catch is I have to trade in by August 29. What should I do?

Added (1). To get the new iphone 5 whenever it comes out

Why would you want to trade in a phone you just got 3 months ago?

$415? They are only $148