Please, please, please do not use vinegar to clean leather, period. Vinegar is a strong acid with a pH around 2.4, and can easily damage fine leather goods. Vinegar has some good cleaning qualities, but its not good for soft surfaces. Leather can easily be cleaned by mild detergents that have a slightly alkaline pH. You really want to use a leather cleaner that is designed for cleaning leather goods.
I clean a lot of leather in Tampa FL and I can tell you that leather is harder to maintain properly then other coverings. Leather is composed of tiny indentations called the grain, which is what determines the quality of the leather. For a good leather cleaning the grain needs to be cleaned out and oils removed. It's important to understand the leather cleaning involves removing the oils from the surface and it change the texture and feel of the leather. After cleaning leather it needs to be conditioned or protected. This video shows no steps of conditioning or protecting the leather grain after cleaning. I recommend protecting the leather after cleaning.
Leather protectants help seal the grain, keeping it dry and pliable. It will also add some oils back to the surface to replace the ones stripped away by the cleaning process. Make sure to always use a separate protecant after leather cleaning to make sure the leather doesn't dry out and age prematurely.