I bought the GOTY last night and was playing a bit. Ironically seeing this thread this morning made me curious as while playing last evening I actually noticed more blood and bullet wounds than I remember previously.
Perhaps it is a coincidence or the lighting change of the levels. I was just messing around exploring Bangkok and decided to go on a killing spree with different weapons. Blood splatter was on walls everywhere. Then I went to Sapienza and went on a shotgun spree and again I noticed more bullet wounds and blood than previously.