if you are promoting any media related project then video marketing will be more useful otherwise article marketing is the best way to get backlinks, anchor link and targeted traffic as well.
IMHO, articles are still important as they are liked by search engines. It's easier for search engines to crawl for keywords and index the content. On the other hand, videos are liked by human. Video marketing is going to be HUGE. eMarketer reported that 52% of web traffic is video. The New York Times has reported that more than 70% of all web visitors watch online video. The average YouTube visitor spends 27 minutes watching video every single day. So I think video is the future way to go.