Describing the metastable equilibrium states at the quasi-static glass transition temperature of organic liquids with the help of the “Frenkel model” as “voidsaturated-systems” it turns out that these states can be thermodynamically characterized by a common value of the specific excess entropy (“iso-excess-entropystate”) if an “iso-excess-volume state” at this temperature does exist. Therefore pronounced short range ordering producing the same specific entropy content of the total system should be apparent at this temperature independent of the structure of the molecules thermselves. This hypothesis can be shown to be valid for various polymer solvent mixtures too. An understanding of this general result may be related to criteria of stability of metastable quasi-static organic liquids at their temperature of glass transition.