Adjusted the wording of the last paragraph and continued:
So, now to the comparison for cash games. Let me caveat this by saying that poker is poker, and in a vacuum your going to play poker the same way. Your approach/philosophy to playing a hand shouldn't change, its the format and environmental factors of that format that will impact your game. As tourneys go on, you are almost certain to have your decision making impacted by a variety of items out of your control - blinds, stack size, and pot size for example. Your opening range and style of play will often vary based on these factors.
Cash games rarely introduce these types of factors in decision making. Pot committed scenarios do come up, but not without a lot of action throughout the entirety of the hand. So you can conceivably go multiple sessions without ever being pot committed. As such, cash games must be approached with extreme patience. They can seem less exciting to a tourney player as all-ins are more rare and many hands never reach a showdown. Additionally, understanding relative hand strength is a must. I often see tourney players over-value their hands in cash games when facing lead out bets or all-ins. There are no environmental factors forcing people to make moves with weaker hands, so players need to adjust their opponent ranges accordingly.
To me, the most important difference is post-flop play. Players need to focus on their opponents betting patterns/lines and really try to understand what they are doing. There are more complexities to betting patterns in cash games, mainly due to the same factors mentioned before.
I could go on but I am tired of typing