Methinks there's be some aftermarket tuning support for that V6. Like the Ford Ecoboost, you should be able to flash the ECU and extract more power out of the TTV6.
That being said, I've heard that Toyota ECU's are notoriously hard to crack, so we'll see if/when it happens, and what the gains are.
The V8 wasn't really tunable. Outside of sticking a supercharger on, there weren't many options for getting more power out of it.