That wasn't really specified but that being said, I'm pretty sure I've sustained more than one G on the skidpan (even if I was merely riding shotgun) ... but I have no gauge/G-force meter in my track car.
I found it quite coincidental that Lexus start advertising the LFA right after the Top gear episode on Monday On another note, since they are all already pre-sold (at an exorbitant price), it is presumably only advertising the Lexus brand as being performance-oriented (despite the volume sellers being IS250's) in a similar way to how Nissan implants the 370z and R35 image into all customers... even those buying the Micra.