History is partly based on moving to moving to new process nodes to allow you to do more stuff with less power. Unfortunately Kal-El will be running on the same 40nm process that current Tegra processors are running on. To the extent that the device can quickly wake up, get stuff done more quickly than a Tegra 2, then go back to sleep it might be more power efficient than last generation, but not with something like this demo.
EDIT: Remember, the previous generation had two A9 cores, and this one has four A9 cores. My vague impression is that the A9s in Tegra 2 really are more power efficient than the A8s in the original Tegra, but we won't see a transition like that in this generation.
Even worse for Tegra 3, it looks like it's going to start shipping around the same time as Qualcomm's Krait which is 28 nm process. Nvidia needs to ride herd on their supply chain, they keep missing their ideal launch window by a few months.
Qualcomm won't have quad core Krait chips until a year later (mid 2012), so it won't compete with Tegra 3 in performance by far. By mid 2012, Tegra 4 will come out at 28nm as well.
But yes, I agree it would've been nice if they could've moved to 28 nm now, too. But I think Qualcomm will really remain behind performance in the next few years. Their custom Scorpion cores are weaker than Cortex A9 now, and I assume Krait will also be weaker than Cortex A15 which Nvidia, Apple and others will use. It's probably the reason why they could go to 28nm so fast, too.
Qualcomm has been right in the thick of it over the past 18 months. They're leapfrogged atm but they also just bumped their GPU and are about to start shipping 1.5 Ghz chips that appear more then competitive:
EDIT: Remember, the previous generation had two A9 cores, and this one has four A9 cores. My vague impression is that the A9s in Tegra 2 really are more power efficient than the A8s in the original Tegra, but we won't see a transition like that in this generation.