This is an announcement for the paper "A note on fragmentability and weak-G_delta sets" by V. P. Fonf, R. J. Smith and S. Troyanski. Abstract: In terms of fragmentability, we describe a new class of Banach spaces which do not contain weak-G_delta open bounded subsets. In particular, none of these spaces is isomorphic to a separable polyhedral space. Archive classification: math.FA The source file(s), frag-w-gdelta6.tex: 18701 bytes, is(are) stored in gzipped form as 0812.4690.gz with size 7kb. The corresponding postcript file has gzipped size 70kb. Submitted from: smith@math.cas.cz The paper may be downloaded from the archive by web browser from URL http://front.math.ucdavis.edu/0812.4690 or http://arXiv.org/abs/0812.4690 or by email in unzipped form by transmitting an empty message with subject line uget 0812.4690 or in gzipped form by using subject line get 0812.4690 to: math@arXiv.org.