Adami uses technicals, at least he talks about them on the show.
Pete, the options trader, uses volatility and follows buy/sell interest as well as news. That is what the Optionsmonster website is all about, finding tells within the options activity.
Macke seems to use more fundamentals in his trading against the backdrop of overall market sentiment.
Karen, she seems more of a money manager type. Fundementals would be more of what she would look at in her analysis.
Overall they all seem to be swing traders when they trade. Pete is probably the closest to a pure trader out of all of them. They make some interesting observations, but overall the show is entertainment. They do serve as a good news source regarding the markets and what is going on with some of the whales and larger funds out there. Dylan used to follow the money flows on Bloomberg when he was there and Fast Money seems to be a reflection of this background.
Good Luck!