Worst. Secret. Ever. Ah well, it's public knowledge now, with Pandemic finally releasing the first details on their upcoming Lord of the Rings game. Called Lord of the Rings: Conquest, it's a "spiritual successor" to the studio's previous work on the Battlefront series, and as such will be a fairly similar title. Except there'll now be up to 150 combatants on-screen at any time, with players able to choose from "practically the entire universe" of LotR characters and races.
There'll be two singleplayer campaigns to play through, one presumably "good", the other based on a scenario where Sauron actually gets his hands on the One Ring. As for multiplayer, while there'll be 150 characters on-screen, it'll support only 16 players online at any time, though it will also feature four-player co-op play, including - awesomely - four-player splitscreen co-op on the same console. Game's due sometime in the fall, and will be hitting the 360, PS3 and PC.
I was originally a little sceptical about this whole thing, but 150 guys duking it out on a battlefield (ie sections of Helm's Deep) might - if they can get the level design right - totally nail that LotR "big battle" feel.
UPDATE - Pandemic got in touch with us this morning to let us know that despite the original IGN piece reporting the game would support 8-player online multiplayer, it will in fact support 16. Which should be much more to your liking.