Out by half. Opera claim an active 300m users per month[1]; it doesn’t look like Netscape ever exceeded 130m (combination of [2] and [3]).

[1] http://business.opera.com/press/faq

[2] http://www.allaboutmarketresearch.com/internet.htm

[3] http://commons.wikimedia.org/wiki/File:Netscape-navigator-us...