I’ve just uploaded version 3.2 of achemso to CTAN, and also sent it off the the American Chemical Society. The development for v3.2 has mainly been about making using the package easier for end users. I’ve removed a lot of dependency on other support packages, so that it only uses very standard LaTeX packages (things like float and caption). I’ve also made the package cope better with older versions of xkeyval, by using only a subset of the functions provided there. There are a few bug fixes as well, plus a new environment for graphic TOC entries. Hopefully, this makes life easier for manuscript authors.