On the other Toyota models that had the "floor mat" recall last year, they cut off about 1" (give or take) from the bottom of the gas pedal. The gas pedal assembly is actually pretty simple - it's a box mounted to the firewall with an arm sticking out of it. The arm is a single, solid piece of plastic that also includes the flat part where you put your foot. Toyota made metal templates specific to each model that the tech uses to mark where to cut, and then they just cut the plastic along the line. A little sanding to clean up the rough edges and they're done. I have seen it done, and it's not as bad as it sounds because it's plastic and it cuts pretty easily. If customers are unhappy with the cut job *after* it has been done, they can complain to the service manager and request that a new pedal could be ordered through Toyota. Toyota will replace the whole thing at no cost to the customer, but only if the cut job came out bad.
On select models getting this done, they also flashed the engine ECU with a new program that includes a brake override system. The override will cut engine power when the brake is applied under certain circumstances. This set of conditions must exist:
1. The throttle is more than 1/3 open (usually because the gas pedal is depressed)
2. The vehicle is moving more than 5 MPH.
3. The brake is then applied firmly while 1 and 2 are both true.
If the override kicks in, it is released when the brake pedal is released.
If you press the brake pedal first and then apply gas (trying to start uphill, for example), the override does nothing. The override also doesn't function in 4LO on 4x4 models.
Finally, the dealer is supposed to inspect the vehicle and remove any floor mats that are not properly secured, or floor mats on top of other floor mats. Toyota has only replaced their OEM all-weather floor mats with a different design as part of the recall; the carpet floor mats are not changed.
Once the recall solution has been announced, keep the recall in mind if you ever have to go to a dealer and don't want the work done. A lot of dealers just do recall work automatically while they have a car because it's usually easy and it's work that's paid for by Toyota instead of the customer. In other words, it's revenue for the dealer. You'd have to tell them in advance that you don't want the recall work done.