For some reason (likely because Verizon is so hard-nosed about their stuff) it took Samsung quite a bit longer to release the kernel source code for the Verizon version of the Samsung Galaxy S III. By last week, the kernels for all the other major manufacturers had already been released, so it was a little odd that the Verizon version was taking so long. Luckily, that has changed as Samsung just released the Verizon version. Of course, savvy developers across the interwebs have already rooted the device, but now it will be a whole lot easier and faster for our devs to accomplish so much more. Here's a link below.
Source: Samsung Open Source