The game was announced as simply "Lords of Shadow" without the Castlevania name. This was done to keep the game's announcement from upstaging the release of Castlevania Judgement, as well as keep Konami's plans to change the series direction a secret.
A scroll can be found in the second level of the DLC chapter "Resurrection". It deals with 'the Beast of Aaargh', a reference to the movie Monty Python and the Holy Grail.
There is a reference to the game "Portal" in a dead knight's scroll. It reads, "[...]I can happily declare that the 'Cake' is not a lie."
The music played in the "Music Box chapter" is a remix of "Vampire Killer", a staple track in the Castlevania series.