This happens with TV episodes, too. "Operation: Annihilate!" is often listed in reference sources with a colon, but the actual onscreen title employs dashes, as in "Operation--Annihilate!"
And here's another issue: movie and TV credits often used to place their titles in quote marks, although this convention has largely fallen by the wayside. So are the quote marks part of the title, or just an old-fashioned typographical choice?
For example, is the old Errol Flynn movie Captain Blood
or "Captain Blood"
(as the title actually appears onscreen)?