I know the death animations don't really have much bearing on the actual gameplay itself, but if I'm going to be spending a majority of the game killing stuff, I want it to look and feel interesting. San Andreas came out in 2004, and at that time, and even before, ragdoll physics were being widely used, along with proper aiming systems, but the games barely improved from a technical standpoint as the series progressed (sans GTA IV), meanwhile you have game's like True Crime which, again, from a technical standpoint, looka much better. And that came out in 2003.
Gonna play more Killzone Mercenary. Almost at the end now. Maybe after I'll play some more Doom with Brutal Doom.
I love shooting peeps in the legs and watch them stumbling around. The physics engine in it is cutting edge since everyone is in full ragtime mode all the time.