his DMCA notice (and we last wrote about the situation). Vine's TOS prohibits infringing content and permits Vine to remove it "without prior notice and at our sole discretion." That's all standard language for a social media site. However, we haven't seen any news about other popstars chasing down Vine videos. You can sort through DMCA notices at Chilling Effects but a cursory look doesn't reveal any Prince-style complaints. (The notices would go to Twitter, Vine's owner.) We also don't see any indication that Vine is using a Content ID system to flag material.
Is seven seconds a fair use? There are no size, shape, or time limitations that excuse an infringement, although the shorter the segment and the more transformative it is, the more likely it will be excused as a fair use. Your proposed music criticism blog (with seven second snippets) also sounds like a fair use. And if you have a strong fair use position, you can always push back against a DMCA notice. But, if threatened with a lawsuit, speak with an attorney before throwing down the gauntlet.