Somehow the translation of the blog templates doesn't work. I do have the files in blog/lang/*.php, and they contain the right references to the templates. But everybody sees the blog controls in English. Our CMS is still translated, so it doesn't seem to be a global problem.
Thanks Henk, I should have seen that before I patched all the templates concerned and added the "identifier>.ss." to the "_t(<i18n-name>, <string>)" calls.
Testing and including your patch as fast as possible in the released version is a must for SS if they care about the International - non English speaking country - users. Most normal users will not be able to fix this, or workaround, and then it is a showstopper.