Yudel Shain reports on Chabad influence in the kashrut industry. Here is a brief excerpt regarding Rubashkin:
Rubashkin Meats Many informed observers have noted that, for many reasons, the various "separate runs" of shechita and nikkur at Rubashkin (intended to allow Lubavitch-free shechita for concerned consumers) are all commonly mixed together by the time they leave the processing plant. Until recently (according to reports) only six out of 20 shochtim were non-Lubavitchers. In the past few months, however, the number of Lubavitcher shochtim has dropped to below 50% (seemingly in response to criticism in the kosher market). While obviously not removing all concerns, this does seem to be a step in the right direction.
That remains to be seen.