Oh, you're absolutely right. Unfamiliarity is at least half the problem. It's names that start with the same letter that kill me - even if I know which character is which there's an even chance that I'll call them by the wrong name half the time. And once you start throwing in last names . . . with Wacky Punctuation . . .

(There's a character in the manga Angel Sanctuary whose name I get wrong every time, which is twice as embarrassing because she is my favorite!)