If your fork is stuggling to gain users then it's not really worth forking, I agree. You wouldn't fork for forking's sake. Whatever compelling features are going to win users away from Google Chrome could appear in Firefox or in a hypothetical Mozzila Chromium, but with the latter you're getting effectively free work from Google. And a Mozzila Chromium fork would start off a little better than 0% market share just on hype, I think, eh?