I never thought it was that good but it really is and not only for Nikon raw files but also with any .jpg photo :)
I use DXO for correcting the lenses distorsion and then NX for converting raw files into .jpg.

For more information: http://www.capturenx.com
You can download a Windows 30 days demo at http://support.nikontech.com/cgi-bin/nikonusa.cfg/php/enduser/std_adp.php?p_faqid=14361&p_created=1185999117&p_sid=4Ji_4zIi&p_accessibility=0&p_lva=238&p_sp=cF9zcmNoPSZwX3NvcnRfYnk9JnBfZ3JpZHNvcnQ9MzoyJ nBfcm93X2NudD0xMDk1JnBfcHJvZHM9JnBfY2F0cz0mcF9wdj0 mcF9jdj0mcF9zZWFyY2hfdHlwZT1hbnN3ZXJzLnNlYXJjaF9ub CZwX3BhZ2U9MQ**&p_li=&p_topview=1