If you mean to literally crap my pants then it would have to be fucking huge, I can't think of anything though. Closest would be if Miyamoto admitted he had his head up his ass since after the release of Metroid Prime and actually focused on quality again instead of what makes a quick buck. Then announcing a new Metroid that doesn't focus on clogging up the game with cinematics, crappy dialogue and missions. Also, getting rid of the ZSamus design as well.
Probably the same reaction if HAL noticed how shit Brawl is and mentioned a new Smash Brothers that would try to really improve on the game play in Melee instead of watering it down to death.
I would be really really happy to hear about that, definitely worth losing control of your bowels over.