I'd be amazed if the 24-70 II will be sold as a manufacturer kit. I'd also be amazed if buying it as a kit from a reseller like B&H or Adorama would save you more than a hundred bucks or so.
And I have a hard time believing that saving a hundred bucks is really worth the wait for somebody wanting to spend several thousand on a new camera, especially somebody who already has invested thousands in equipment.
The 24-105 is slow, yes, but it's optically excellent, has IS, and has a significantly longer reach than the 24-70. And the 24-70 is only one stop faster, which isn't all that much in the real world.
My advice? Get the 5DIII with the 24-105 kit. If you really need that additional stop, get the Tamron 24-70. The Tamron is better optically than the Canon 24-70 I (which is rightfully a legendary lens), costs half as much as the 24-70 II, and has IS.
Either option gets you the camera in your hands today, which is worth a lot more than a hundred bucks. And, either option will save you a grand over the 24-70 II -- almost enough to get the 35 f/1.4.
Should you regret your decision when the 24-70 II finally hits the streets, no worries. If you went with the 24-105, you'll be able to sell that for at least as much as it cost you to buy it in the kit. If you went with the Tamron, the depreciation will be far less than it would have cost you to rent the lens. Either way, you'll have had the full use of the camera and lens for the period and you'll come out ahead financially.