This is an announcement for the paper "Special symmetries of Banach spaces isomorphic to Hilbert spaces" by Jarno Talponen. Abstract: In this paper Hilbert spaces are characterized among Banach spaces in terms of transitivity with respect to nicely behaved subgroups of the isometry group. For example, the following result is typical here: If X is a real Banach space isomorphic to a Hilbert space and convex-transitive with respect to the isometric finite-dimensional perturbations of the identity, then X is already isometric to a Hilbert space. Archive classification: math.FA Mathematics Subject Classification: 46C15; 46B04 The source file(s), SSNSb.tex: 30955 bytes, is(are) stored in gzipped form as 0809.1789.gz with size 9kb. The corresponding postcript file has gzipped size 74kb. Submitted from: talponen@cc.helsinki.fi The paper may be downloaded from the archive by web browser from URL http://front.math.ucdavis.edu/0809.1789 or http://arXiv.org/abs/0809.1789 or by email in unzipped form by transmitting an empty message with subject line uget 0809.1789 or in gzipped form by using subject line get 0809.1789 to: math@arXiv.org.