Oh, it's ON. In one of the best brand-on-brand tweets ever, cinema chain AMC Theatres on Tuesday expressed its displeasure with Oreo after the Nabisco brand asked fans if they ever sneak cookies into a movie. "NOT COOL, COOKIE" admonished @AMCTheatres, which sparked an impressive 200-plus retweets. Credit for the post goes to Shane Adams, interactive marketing manager for AMC. While it's unlikely that this will spark any sort of long-term rivalry, it's still nice to see a company having some fun with another brand in the vein of Taco Bell and Old Spice. It's also a telling example of why @AMCTheatres has 136,000 Twitter followers, compared to Oreo's 53,000. Where are those 28 million Facebook fans to defend you now, Oreo? Hat tip to Deb Ng for sharing on Facebook.