Likely pressuring Nokia (NOK -1.9%) today is a downbeat note from Goldman's Rick Schafer. Schafer, who's slashing his 2013-2015 revenue, EPS, and smartphone volume estimates, calls the feature set of the Lumia 720 and 520 "relatively undifferentiated," and notes a recent Goldman survey indicated "only around 41% of Win Phone owners chose to buy another Win-based device over the last six months." (earlier)