If I remember right John McTiernan is/was slated to direct a big screen Honor Harrington flick. I like that choice if he can channel some of his old school Die Hard/Predator/Hunt for Red October vibe into the project.
A Honor movie could have the greatest space battles of all time if they find a way to slip in the exposition that explains the tactics of what is going on. We've never really had that concept in sci-fi because it requires a ton of exposition and lecturing that would slow the story to a stand still. Honorable mention to Wrath of Khan and BSG for trying however.