The GTX 780 Kudan is the company's top GTX 780 model, featuring a custom PCB design and a non-reference cooler that has a total of three expansion slots. The cooler features three fans and five heat pipes. The card would be built from higher-quality components, and that, in combination with being powered by two 8-pin PCIe power connectors, should allow the card to have a lot more overclocking headroom than reference models. To accomplish this, the card will have a much better VRM design than the reference models.
The GTX Titan Ultra Edition is nothing more than a reference model of the GTX Titan with a water block on it and a factory overclock. The company gave no word on the level of the overclock, though. If the card does hit retail, we can expect it to cost a decent bit more than the reference GTX Titan's MSRP.