Nerval's Lobster writes: "Twitter has rolled out Vine, a free app for iOS devices that allows users to shoot and post short videos. Twitter’s strategic focus on brevity—the company has long resisted calls to lengthen Tweets beyond the current 140-character limit—extends to Vine videos, which can only be six seconds in length. “Posts on Vine are about abbreviation—the shortened form of something larger,” Dom Hoffman, Vine’s co-founder and general manager, wrote in a blog posting. “They’re little windows into the people, settings, ideas and objects that make up your life.” It’s easy to see the Vine acquisition as part of Twitter’s larger push into multimedia. The company launched a muscled-up photo service Dec. 10, complete with Instagram-style filters and editing tools. That photo launch came on the heels of an escalating battle with Instagram, the Facebook subsidiary, which decided to disable photo integration with Twitter; that same month, Yahoo also decided to jump into the fray with a new Flickr app for iPhone, complete with special filters and the ability to post images to various social networks."