I hear it's really, really short, no trophies and not worth the $5 or so it costs. I have some PSN money in my wallet I'm dedicating to DLC since if I keep it sitting around I'll just buy more games I won't play... I want this account to have a cleaner list of games/trophies with more platinum's and 100%'s. I have pretty much all the DLC I'll want (Uncharted 2, GTA IV, LittleBigPlanet, etc), so I'm not entirely opposed to the idea of trying The Taxidermist.
I enjoy the idea of owning only a handful of games that I play through completely, DLC and all.
Any good things to be said about this DLC though? If no one around here has it, maybe I'll just try it for myself and report back with my impressions. I love Heavy Rain, so I'm sure I won't be horribly disappointed... though $5 for 5-10 minutes of gameplay (or so I hear) is pretty weak.