An important response to the current discussion on avalanche survival:

Falk, Bruller & Adler- Kastner's work on avalanche survival is a solid
scientific study.  It is especially valuable because their data show
that survivability during the first 15 minutes is much greater than
previously thought.  However, some of their conclusions we feel are
flawed, and all of you missed their most important conclusion regarding
avalanche rescue beacons.  The only way to find a buried person within
15 minutes is by using a beacon.  Most people other than ski patrols
and guides are not "practiced" enough with their beacon to save a
life.  In fact, in the US the buried victims chances of dying are 10
times greater in the backcountry than in a developed area.  DON'T GO
FOR HELP ---STAY AND SEARCH UNTIL YOU HAVE DONE ALL THAT YOU THINK IS
POSSIBLE.  Even if there are 5 searchers and you send 1 out to get help
the group's efficiency has suddenly dropped 20 %.  Keep searching!
You are the victim's best chance to be found alive.  Falk's group also
concluded that burial depth is not an important factor in survivability
since the deeper the burial  the greater time required to dig, thus the
longer the rescue.  While their rationale is true their conclusion is
false.  Many more people survive shallow burials than deep burials.  In
fact in the US no one has survived a burial deeper than 6 feet.  The
reason is simple.  The deeper the burial, the greater the mass of snow
and the less likely a victim can create an air space.  in deep burials
(deeper than 6') a victim cannot expand their chest to breath because
of the crushing weight of the snow.  The discussion of cell phones is
interesting, but as Clyde said, they are only another rescue tool.  In
Colorado there have been 2 cases where cell phones were used to report
avalanche accidents immediately after the event.  In both cases victims
were found almost immediately and helicopters, trained rescuers and
advanced life support equipment were on the scene with in 15 minutes.
In both cases the victims  (3) died.  Here are our suggestions of what
you can do to maximize your chances of survival.

1)  Keep learning about avalanches, learn to recognize and evaluate the
clues to dangerous conditions.
2)  Keep off steep slopes when conditions are dangerous.
3)  Buy a beacon and practice practice practice,  make sure your friends
do too.
4)  Form a rescue plan with in your group at the trail head,  ensure
beacons are working and are compatible frequencies.
5)  Buy a big stout shovel and trade it with your partner for his little
one so he can dig you out fast.
6)  Travel as if there will be no outside help.  Take responsibility
for your self and your actions.  Regarding Falk's research we are
surprised by the high survivability (93%) during the first 15 minutes.
The US data show 85% during the first 15 minutes.  In the US more
victims collide with trees during avalanches than in Europe.  Lastly
their study did not look at injuries suffered by avalanche victims.

Dale Atkins,  Avalanche Forecaster, Colorado Avalanche Information Center
Steve Conger, Editor, the Avalanche Review