This is an announcement for the paper "Metric characterizations of some classes of Banach spaces" by Mikhail I. Ostrovskii. Abstract: The main purpose of the paper is to present some recent results on metric characterizations of superreflexivity and the Radon-Nikod\'ym property. Archive classification: math.FA math.MG Mathematics Subject Classification: Primary 46B85, Secondary: 05C12, 20F67, 30L05, 46B07, 46B22 Submitted from: ostrovsm@stjohns.edu The paper may be downloaded from the archive by web browser from URL http://front.math.ucdavis.edu/1411.3366 or http://arXiv.org/abs/1411.3366