The new stage of game design to do first...

There is nothing new about Pretotyping except using the word.  At Gameloop Boston #gl11, during the Prototyping panel professional game designers discussed the various methods they use to prototype a game.  Flash, Game Maker, Unity are all the rage right now in big design companies to get their ideas down into a playable form before coding a new game.  And then there was one guy at the panel whose main prototyping experience was using a D&D dry erase battle mat before ever coding anything...  Yeah, that was me.