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:
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.