Netscape 6.0 is finally going into its first public beta. There never was a version 5.0. The last major release, version 4.0, was released almost three years ago. Three years is an awfully long time in the Internet world. During this time, Netscape sat by, helplessly, as their market share plummeted.
It's a bit smarmy of me to criticize them for waiting so long between releases. They didn't do it on purpose, now, did they? Well, yes. They did. They did it by making the single worst strategic mistake that any software company can make:
They decided to rewrite the code from scratch.
It’s harder to read code than to write it.
This is why code reuse is so hard. This is why everybody on your team has a different function they like to use for splitting strings into arrays of strings. They write their own function because it's easier and more fun than figuring out how the old function works.