The reigning queen of Polish skiing is officially back on top of the world. After a slow start to her 2011-2012 campaign, Justyna Kowalczyk owned the Tour de Ski in January, then followed up that performance with her victory on Thursday in the Moscow city sprint. In doing so, she took over the yellow bib that represents the top level of World Cup success. In front of a home crowd, Russian teammates Natalia Korosteleva and...