Command line script for getting and setting a default browser (HTTP handler) in Mac OS X.
As there seems no other elegant way of doing it you need some Objective-C code.
The code uses Launch Services. More info on Launch Services Reference
Open the XCode project and build it or download the build/defaultbrowser and put it somewhere
in your path. chmod +x defaultbrowser is probably also necessary.
You can set the default browser with:
defaultbrowser -set chrome
Running defaultbrowser without arguments shows the current setting.