"That's not a knife, THAT'S a knife!"
-- Crocodile Dundee
The other day I was on the giving end of a bad beat when I decided that my AKo was good enough to get involved in a preflop raising war between 2 other LAG's. We ended up all-in 3-handed with the following holdings (and preflop equity) :
LAG #1 : As Ah (93.1%)
LAG #2 : Ad Kc (3.6%)
Myself : Ac Ks (3.2%)
Much to the dismay of everyone present, I took down the huge pot with a club flush. THAT is a bad beat.
Matt Matros, a player with a strong math background who I highly respect, talks about his WSOP experiences in Card Player (August 8, 2012). He recounts a hand where his KK was all-in preflop against AKo and an ace came on the river. This is a 70:30 situation and on a bad beat scale of 1 to 10, I would give it a 5. Yet he refers to it as a "huge beat" and a "vicious beat". Later on he describes losing a preflop all-in with his A9o vs. QJo as a "bad beat". This is a 57:43 scenario, sometimes loosely referred to as a coinflip, hardly a bad beat.