It isn't a rumor, it's already a fact! It comes standard with a 6 speed tranny. Sequential shift.

 

Click here for a view of Getrag 233 internals. It's the Supra 6 speed. Yes, my gearbox. Yes, I rebuilt it myself with all the updated internals after I broke first gear's synchro.

It gives you an idea what's needed to handle a lot of torque. I'm pretty skeptical the 2GR-FSE will respond to modifications make the same kind of power a modified 2JZ-GTE does though.