If you are trying to differentiate the two clubs cosmetically, the new 710 AP1's will say 710 on the hosel, the cavity has been redesigned and it has an aluminum/elastomer feel system.  Titleist will be in white with a black background vs black with a white background.  The original AP1's were released in Nov. 2007 and carried through to Nov. 2009 when we launched the new 710 AP 1 irons.

Performance wise, due to the newly designed cavity, the sound and feel is hotter and more lively.  We have increased the MOI for more forgiveness and the new thin face will give you a higher ball speed.  On the shorter irons, we have shortened the blade length, made the top line a little thinner and decreased the visual offset for a more pleasing appearance.  If you would like more information, give us a call at 1-888-TITLEIST.

Cathi,

Thank you for the information.  I am thinking about purchasing a new set of AP1s and wanted a way to make sure I could verify the purchase of the new version.  Now I can be sure I get the right clubs.

Ronald M