I recently oversaw the development an ecommerce site (actually a merge of dotlrn and ecommerce) for the Boston Museum of Science. We developed against OpenACS CVS so the changes have been committed.
The site launched last August, so that was before the OpenACS 5.2 was officially released, but we were using 5.2 branch ecommerce (ie - a close predecessor of the release) so it should be pretty close to being compatible if it is not already so.
Carl also just told me on AIM that he plans to move MGH from this version (or close) up to the official 5.2 in Jan.
