@the OP.
The iPhone 5 will be an upgrade compaired to the iPhone 4S, yet we are taking guesses here about what the exact upgrades will be (probably 4g/LTE, iOS 6 and a different exterior).
How it will exactly look? We don't know.
What will be the new hardware? We don't know.
So what do we really know?
That the "4" and "4S" will not become obsolete when the "5" arrives. Yes, it will be better, probably will look different so that it can't be mixed up with the "4" and "4S" by bystanders.
It's not about what the new iPhone can or can't do compaired to the previous, but what YOU NEED it to do that suits YOUR NEEDS.
There are different type of iPhone users/buyers in the world.
Some go through an iPhone every 8 months and the new features will make usage easier, some just want to have the newest and some will chance every other model (or even every two models).
Since "package-selling" is/was illegal in Belgium, I had to pay 750 (740 for the iPhone, 10 to switch to a mini-card) for my unlocked iPhone 4S, so at those prices, it will be the "5S" before I even think about upgrading.
Luckily all the features that the 4S has are enough to get me to fall 2013.
Enjoy your iPhone 4S, Apple Inc will be in the telecom business for a long time so there will come enough models for you to buy, even if you skip from time to time a model
