This is an announcement for the paper "Some new characterizations of Banach spaces containing $\ell^1$" by Haskell P. Rosenthal. Abstract: Several new characterizations of Banach spaces containing a subspace isomorphic to $\ell^1$, are obtained. These are applied to the question of when $\ell^1$ embeds in the injective tensor product of two Banach spaces. Archive classification: math.FA Remarks: 27 pages, AMSLaTeX The source file(s), new-char.tex: 120502 bytes, is(are) stored in gzipped form as 0710.5944.gz with size 35kb. The corresponding postcript file has gzipped size 163kb. Submitted from: combs@mail.ma.utexas.edu The paper may be downloaded from the archive by web browser from URL http://front.math.ucdavis.edu/0710.5944 or http://arXiv.org/abs/0710.5944 or by email in unzipped form by transmitting an empty message with subject line uget 0710.5944 or in gzipped form by using subject line get 0710.5944 to: math@arXiv.org.