T-Mobile announced today that CEO Mike Sievert will step down effective Nov. 1 and be replaced by current Chief Operating Officer Srini Gopalan. Sievert will continue with the company as vice chairman and also serve on its board of directors. The announcement comes as T-Mobile is soaring in the mobile marketplace. A CEO shift often indicates problems for a company, but in this case, all outward signs point to an orderly, planned succession. It should have little impact on T-Mobile customers, but time will t ...