The Specialest Little Ninja
Mark of the Ninja was one of my favorites. And in the sense that it preserves the genius gameplay formula and design talent of the core game, the Special Edition's bonus level is a fun little diversion. But as a value proposition, the Special Edition DLC is a hard sell.
The new mission is good, but not the best, and it's the only new one. The other additional content, items and a costume, aren't meaningful at all when weighed against what's already in the game. And the developer commentary, while cool, is no better - actually, less informative - than what you could get by reading a Gamasutra article or any given post-mortem.
There's a fun hour or two of bonus-level in here, but otherwise the Special Edition DLC is utterly lacking in substance.