Matros revealed this when he tweeted a response to a gamer who'd asked about how the implementation of Battlerecorder would work. Matros messaged back, "@DJNood game is not launching with battlerecorder".
The reason for its omission was not revealed, but a while ago, Patrick Back hinted that resources at DICE for Battlefield 3 were getting thin and they had to decide on what features to cut or go overbudget. According to Back, "Patching of this game and updating, if it’s Battlelog or the core game, that’s a big, long-term engagement. We really want to stay in the game post-launch. From an economic standpoint, that’s not the cleverest thing to do, but that’s not why we make games. We want to make games that we can be proud of, and releasing a game of this magnitude… it’s quite a big game. We know that we won’t hit 100% at launch. We won’t be able to say “It’s perfect.” Better to release it than to wait another year. Release it, and make sure we follow up on it. We’ve been shipping so many Battlefield games that we know that people will keep playing it. If it’s good enough, they’ll keep playing it."
Battlefield is due to be released on PC, Xbox 360 and PlayStation 3 this coming November.