What would be worse, ocean or land impact?
I think a land impact. Sure with an ocean impact you get 3000 foot waves traveling at 1200mph in every direction. Oh, yeah and it rains ocean-floor mud for months over the entire globe. Localized weather is screwed as a result of the hugh-normous...
I don't want to kick a hornet's nest or anything, but...
Fallout was originally based totally on GURPS. There was a falling out between Steve Jackson and Interplay that resulted in the GURPS name being removed from Fallout. This didn't effect the underlying mechanics of the game design...