Netscape and Mozilla may be similar but so much functionality has gone into Mozilla since version 1.0 that Netscape is missing out on. With AOL/Time Warner signing a 7 year agreement to use Internet Explorer in their software, it leaves you to wonder what will happen to Netscape because after the version 5 blunder, they will never regain their market share or even a slight portion of it. Mozilla will most likely continue on if AOL /Time Warner divests of the division but it won't have the resources it has today.
Firebird will be the browser in the Mozilla Suite as of version 1.5 as well which will further remove it from the legacy of Netscape.
I also have a question - Does the Windows version of Firebird do automatic searching on a page? To find out click anywhere in the window and start typing to see if it highlights text as you type. Very useful feature in the Linux version.