On a more serious note:
Basically, rooting gives you superuser access (Administrator or the like) of the phone that lets you fiddle with all the toggles and switches that you never knew were there. Doing this allows you to put on custom software, including full-on ROMS - amongst other things - (which can be found on the XDA forums) on your phone. It's definitely not something for the (mythical) average user to go doing as it could brick your phone if it goes south.
It got planted in the weed garden
So Iburst has gone the same way as Neotel and Sentech... Iburst=Neotel=Sentech(R.I.P)