It is coming out soon!
From:We interrupt this all-night period of not-being-at-work to inform you that 4J Studios has polished off Minecraft Xbox 360 update 1.8.2 and sent it to Microsoft for certification testing. Assuming Microsoft deems the crazy, glorious thing fit for public consumption, the update should be live in a week or two. No guarantees, mind.
"We've handed over the final 1.8.2 build to Microsoft!" the studio tweeted just now. "They'll run some confidence tests then put it into Certification Testing."
The new update adds Creative Mode, Superflat world options, a hunger gauge and new mobs, among other things, and will be entirely free to download. Read all about it in our Minecraft Xbox 360 update 1.8.2 guide.