Pros
Job security; lots of days off; great pay; comradery...If there's another job you want to learn or if you want to add to your current skills, there are plenty of opportunities for you to do so. The USAF is the branch that is most similar to working in the corporate world; it can be really laid back. They also pay for all your training. You get lots of benefits and discounts. You can see the world at little cost. And the memories are forever.
Cons
You can be separated from family for long periods, but thank goodness for skype. You can't quit when you decide that you don't like your job. They can work you whenever, wherever, and as much as they want, and there's nothing you can do about it. I'd think twice about speaking your mind. Don't even think about talking back; they can decide to make your life a living hell...and again there's nothing you can do about it. (It really pays to quickly learn from other people's mistakes.) Lastly, know that when you sign up, you are signing up to physically defend our country and you may be called to bear arms at anytime...and there's nothing you can do about it. Your life pretty much belongs to them, but I advise being smart about the choices you make while you're in. It helps to do your homework before you make decisions.