Google Chrome goals

A lot of people are wondering why in the world would Google want to release a webbrowser?  We already have 4 biggies: IE, Firefox, Opera, and Safari.  A 5th one just further splinters the market and makes life harder on web developers right?  Actually, what Google is trying to do here is increase visibility of the webkit engine that both Chrome and Safari is based upon.  This also happens to be the engine Google has stuck into it's mobile OS Android.  If Google ever wants to see Android succeed, it has to make sure that it displays the web properly.  The only real way to do this, is to get web developers to code and test against it's webkit engine.  By releasing another browser based on webkit, Google may actually increase the overall web presence of webkit and therefore increase usability for it's Android based devices.  I say this is another smart move by Google.