Smartphone sales may be growing at a steady rate these days but, if NPD's latest numbers are any indication, it looks like they still have quite a ways to go before they become the norm among cellphone users. As the market research group found during its latest survey, less expensive featurephones accounted for an impressive 72% of all new handset sales in the US during the second quarter of the year, which is only a 5% drop even in the face of a 47% jump in smartphone sales (to 28% market share) over the same quarter last year -- a 14% jump in overall handset sales accounts for some of that discrepancy. According to NPD's numbers, the LG enV2 (pictured above) and