Buying advice: Iphone 3G with 18months contract

[Volante]

So I am thinking of getting an Iphone 3G. However, I'm not sure if it's the right time to do so. Do you think there will be a significant bump in specs of the Iphone in the next 18 months? If so, what.

 

[fireshot91]

Yes, its like iPods, they'll come out with a new iPhone every summer, and POSSBILY every MWSF