I know that PC, I'm a Maiden fan. That was just one example. And its not like they really NEEDED to explicitly give credit, its kind of obvious what Steve was reading when he wrote "Rime," "Brave New World," "Murders in the Rue Morgue...
@TL: I would normally agree, but in the case of ITPOE, there are lines lifted straight from the comic, or very, very close. Again, I'm more bothered by the quality of the lyrics than the inspiration for them, but that actually is plagiarism.