I did some debugging on FF, ovi store tries to download 12.0 version of the deb and not the 13.0, and that confuses ovi store client. So someone has fuxored the version numbers either in deb file (then the blame goes to mozilla foundation) or someone has fuxored the version numbers on ovi store backend. I did manage to update my 11.0.1 to 12.0.0 from commandline though.