Mozilla is a rare, if not prefect example of what can happen when minds are allowed to collaborate on a single project that interests them all. As with OS distributions such as Linux and other projects in the same category the increased programing efficiency that can be brought forth by allowing many people to interact with a software code. However overcoming security issues as well as financial issues can bring even the best project to a halt; and thats where it takes a little luck and allot of skill. Both of which the guys over at Mozilla have in spades.
Personally I believe open source is a great Idea, not only to spark competition with products developed by payware companies but also to inspire creativity so that products become more robust and the coding community becomes self aware of how diverse and talented people that aren't necessarily connected with a mother company can be.