Learn how to open your seat belt quickly, then there should be relatively few instances when you would need to cut it. Generally on commecial airliners you lift the latch (rather than push a button as in autos).

When I get on an aircraft (any aircraft whether a big airliner or a small bush plane or helo) I make it a point to consider how I would get out in an emergency (where the exits are and how to operate them). I also take a second to practice opening my seat belt (or harness in a bush aircraft). I pull belt/harness quite snug for takeoff and landing. Learn how to assume a good brace position.

The keys to staying alive are to survive the initial impact, and then to get the f*** out fast!

EDIT: More on why you should assume the crash position if you have any warning:
Crash Survivors Show Pattern of Spine Injuries
Quote:
Many survivors of Saturday's plane crash in San Francisco have a surprising pattern of spine injuries that a doctor says shows how violently they were shaken despite wearing seat belts.
------------snip-----------
Still, Manley said even among those who suffered mild spine trauma, he is struck by a pattern that shows how their upper bodies were flung forward and then backward over the lap belts that kept them in their seats and undoubtedly saved their lives.
------------snip-----------
Meanwhile, Okonkwo said assuming the "crash position" — leaning forward with the head as far down as possible and arms over it — can limit the spine jolting back and forth and offer some protection. It's not clear if any survivors of Saturday's crash had time to do so.


Edited by AKSAR (07/11/13 05:37 PM)
Edit Reason: Additional info
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