So you might be asking yourself if everyone is using it, what is the big deal? WebKit was announced by Apple in 2003 and the company open-sourced it in 2005, meaning anyone can do with it what their code writing skills will allow them. This invariably led to many different permutations of this browser engine, eventually getting better and better until major browsers start using it on their brand.
This might be a good thing to a certain extent, but some developers are concerned about the homogeneous effect WebKit might have on innovation. The argument holds true to a certain extent, but it only goes so far because everyone seems to have their own version designed specifically to make their application better.
As more tools are added to these open source applications they start morphing into an all-in-one product, and the conflict between different companies is the only thing stopping them from implementing a very useful tool. A case in point is WebRTC, where Firefox is willingly participating, but not in WebKit.
This is understandable because revenue sources can be eliminated by adopting some of this technology. WebRTC for example can be applied on any webpage and be used for video conferencing, lectures, making calls and many other applications other companies provide for a fee. There are many complicated issues and eventually they will work themselves out because the market will determine who survives and who perishes.
Edited by Brooke Neuman