The short ATA bows have been the rage for the last few years. By short I mean 33" and shorter.

The biggest advantage is that they tend to be more manuverable....at least that is the thought. In practacality I have never been in a situation with my 36" bow that I thought "If my bow were just 3" shorter, I could have made that shot.
Another advandage is that the shorter rigs tend to be a bit faster lb per lb than their longer bretherin.

On the downside, the shorter bows tend to take longer to get stable than a comparable longer bow. And as a rule they don't lend themselves to as much accuracy as longer rigs (This is one of the reasons you don't see guys shooting indoor spots with a short bow).

What it comes down to is personal preference. If you have not ever owned one, then it is up to you to try them out and determine how they feel to you. I have owned short bows in the past and I find that for me 35-36" is about the optimum balance between shootability and manuverability.

Regardless of what you pick (short, medium or long), one of the newer designs will be light years ahead of a 10 year old bow.