The Samsung sensor has not been tested yet, and the DPreview samples at 3200 are very noisy. On the other hand, the NEX-5N has improved performance on the already very good Sony 16mp sensor, acording to the Imaging Resource's comparaison here:
Sony Alpha NEX-5N Compact System Camera - Hands-On Preview
As for the lenses, I'll concede I envy the Samsung 30/2, but I have not seen many of their other lenses tested. IIRC, their 20mm needs strong software correction, à la Panasonic/Olympus, which is a negative for me.