TechCrunch spoke to NVIDIA about the Tegra 4 and got to hear that Tegra 4 is about two to three times faster than Qualcomm's Snapdragon 600 (present in devices like the new HTC One).
When asked about how much NVIDIA knows about Qualcomm’s updated Snapdragon chipsets, he replied simply enough: “we know a lot.” By his count, the Tegra 4 is about two to three times faster than Qualcomm’s Snapdragon 600 (used in devices like the new HTC One). He went on to say that the top-tier Snapdragon 800 is about 25 to 35 percent faster than the 600, with the implication that the Tegra 4 still comes out on top.
Though his response has based on Qualcomm’s published Snapdragon claims, I’d still advise you to take that comparison with a grain of salt. That’s nothing against Wuebbling, but these sorts of simple comparisons don’t always paint the most accurate picture. I couldn’t reach Qualcomm for response at time of writing, but I’ll update if/when they respond to these claims.