John Bitove is stepping down as chairman of satellite radio operator Sirius XM Canada Holdings Inc., the company said Thursday. SiriusXM Canada said in a press release that Bitove, who among other things is the founder of wireless carrier Mobilicity, will resign from the chairmanship but seek election as a director on the board at the company's annual meeting in January. SiriusXM Canada said its board has nominated current director and former Rogers Media president Tony Viner to become the next chairman....