In the same thread I mentioned above, I picked up a nice little "house" rule for speeding up the proccess of determining whether a mook dies or not. Unfortunately I can't remember the original author to credit him, but if anyone remembers, please tell us.
Basically, you roll percentile dice based on the current HP of the creature when it falls unconscious:
Negative hp...probability of dying
1.................0.39
2.................0.43
3.................0.48
4.................0.53
5.................0.59
6.................0.66
7.................0.73
8.................0.81
9.................0.90
10................1.00