Who woulda thunk it? A global recession leads to belt tightening, and belt tightening leads to fewer mobile data card sales. According to a new report from ComScore, that's exactly what happened at the tail end of last year, where WWAN card growth slowed to just 5 percent compared to 28 percent in Q4 2007. Still, carriers can't grumble too loudly -- after all, at least it grew. In fact, PC data card adoption rose 63 percent overall in 2008, and if any of these 4G services can see rollouts of significance, we suspect 2009 will show