Well I will probable continue to use IE for awhile as my main browser since that is what I'm use to, but FireFox is similar to Netscape (Both made by the same "source" / Mozilla). So if you like the new Netscape, you will probable like FireFox.
The only downside I see is that FireFox does not come with all the plug-in's that IE does, (for example, Macromedia plug-in), so it was an extra [easy] step to download the plug-in.
But so far FireFox seems to load webpages A LOT quicker then other browsers, but I have only started using it. (Plus it comes with a built-in popup blocker)
NOTE: I always like to have at least a few different broswers on my PC. Main reason is I use one browser, and my wife will use a different browser - that way we don't have to try to share "cookies" and stuff. Plus I also like to test all my websites in a few different brosers to check how things look.