What is the craze about these exercise ball exercises?? I'm thinking about getting one if the results are awesome, please share stories!!

The idea is core stability.. as if you do your exercises on the ball you have to use your core muscles to balance and keep in position.. similar idea to using freeweights vs machines and furthermore, using dumbbells as opposed to barbells; as this utilises the most stabilising muscles, such as the rotator cuff  muscles of the shoulder, the forearm for grip and the core to stabilise.

This could be useful if you participate in sport; increasing performance and reducing chance of injury because of joint stability. However, it can actually increase the risk for the actually weight training if you do not focus, as you're more likely to fall or drop a weight.

I haven't bothered using a ball myself...

I like them for abs - and stretching. Not so much for using with weights.

I used one for a few training sessions and just found it awkward really. If you're using weights (I was) you can't lift as much because you'll fall off, and really how is that sort of training applicable to any real life situation?

If you want to work your abs, just do one handed lifts...

Personally I would never use an exercise ball at the gym, it just looks damn strange

Why would you care